Richborough Military Transportation Depot.” by JOHNKERR ROBERTSON, M

156 ROBERTSON ON RICIfBOROUGII hlILITARY [Miuutes of

ilssociate Mentbers. ERNEST DENNIS AVERAY,B.Sc. I FREDERICARTHUR HARPER, M.A. (Eng.) (Lond.). (Cantab.). SIDNEYNORXAN BARRON, O.B.E., EDGARHOWE, B.&. (Eng.) (Lond.). M.C., B.%. (Manchester). NORMANSINCLAIR JEFFREY. SYEDMTJJTABA ALI BILGRAMI. , ROBERTOXELL, M.C., B.Sc. (Eng.) CHARLES ERIC BOAST. HENRYJAMRS NORRISON COTJSENS, LEO VINCESTPEREIRA. R.&. (Qlns.). G~II~~KENITzROUQUETTE. FREDERICKGEORGE ERNEST FORD.I, QEORGE STANLEY. FREDERICKJAMES COLIN HANSON.’ JOIINWILSON, B.E. (Royal).

(Paper No. 4282.)

“ Richborough Military Transportation Depot.” By JOHNKERR ROBERTSON, M. Inst. C.E. THEconstruction of the Port of Richborough was one of the works carriedout under the Department of theDirector-General of Movements and Railwaysfor the transportation of military material and stores, and formed an important point in the extensive lines of communication called into existence by the needsof the Great War. It is not necessary here to trace the development of this department from its beginning in the quartermaster-general’s branch, or to detail the exact position in the great military organization for the prosecution of the war, which was occupied by the directorate responsible for the conception and constructionof the new port and its operations. It is sufficient to state that the Directorateof Inland Waterwaysand Docks (under the Directorship first of Major- General A. S. Collard, C.B., C.V.O., and later of Brigadier-General A. S. Cooper, C.B., C.M.G.) was the directorate in the Department of Movements and Railways under whose control Richborough was developed until its activities extended into every theatreof military operations of the war. From Canadato Mesopotamia, from the Murman Coast to East Africa, on land and on sea, might be met the men and material trained and produced at Richborough, and sent forth to help extend and operate the linesof communication of the advancing armies. Thegerm of theorganization, which later became theInland Waterways and Docks at home, and the Inland Water Transport abroad, lay in the need for the development of transport on the canals of France mcl Belgium in the early days of the mar. This necessitated the provision of men ancl barges for the transport of all

kinds of militarystores, and the construction of fttcilities for loading and discharging cargoes, and the repair and maintenance of canals and barges. Originallythe personnel of theInland Water Transport was accommodated and trained at the depot of therailway troops at LongmoorCamp, and Dover was thehome port from which extendedthe lines of comnlunicationoperated inFrance, while thestores of thisyoung branch of the servicewere housed at Ashford. With the progress of the war the ever increasing demands for barges,which could not be provided from existing shipyards, and the provision of therequisite wharfage from which thebarge traffic could be operated, indicated the necessity for the establishment, at a suitable site, of a military depot capable of carrying out the works required to meet these demands, andat which the entire homeorgtnizittion of theInland Water Transport could be con- centrated. The selection of Eichborough on the €liver Stour for the establishment of the new port lay in its geographical position, relative to the Channel ports and the Continental canal system, the existence of large deposits of sand and gravel, ease of railway access, and the extensive areas available for camps and store yards. The works originally contemplated were of modest dimensions, but with the progress of the war and the increased demands for transportation,the organization and operations of theInland Waterways and Docks rapidly expanded, until on the conclusion of the Armistice :t great military depot had sprung up, consisting of camps, workshops, power houses, shipyards, wharves with extensive basins,warehouses, storeyards, salvage depots,and miles of railwaysconnected with the Continental railway system by a service of train ferrysteamers. It iswith the construction of these works that it is proposed to deal with in this Paper. The new depot lay about 3 miles south of Ramsgate along the River Stour between the town of Sandwich and Pegwell Bay, and covered an area of about 1,361 acres; of thisarea approximately 172 acres were occupied by camps, 271 acresby store yards and salvage depots, and 11 1 acres by workshops and shipyards (Fig. 1, Plate 3).

CAMPSAKD BUILDISGS. The permanent camps and buildings were constructed entirely of concrete blocks manufactured on the Winget block principle, and provided :tccommodation for 14,120 nml.The temporary camps

Downloaded by [ York University] on [16/09/16]. Copyright © ICE Publishing, all rights reserved. 158 ROBLRTSON ON RICHBOROUGH MILITARY [Minutes Of consisted of standard type of wooden sectional huts, and provided accommodation for a further 3,000 menand 523 women. In all, including officers, a strength of about 18,000 was housed in the 512 buildings comprised within the camps, the total floor area of which including dining halls, administration buildings, regimental institutes, etc., extended over 27 acres. The huts and buildings wereall built to standard design anddo not call for anyspecial remark. The main group of camps was provided with a seweragesystem and disposal works, described later.The supply of water was drawn from the Ramsgate and Sandwichsources of supply. The camps were lit throughout with electricity. Owing to thelom-lying and flat nature of the sites uponwhich the camps were located, an extensive system of well-formed and drained pathsand roads had to be provided. The Ramsgate-Sandwich Road formed the main artery throughout tlle camps and works.

MAXUFACTUREOF CONCRETEBLOCES. In themanufacture of the blocks required for the construction of the camps, offices and workshops, two blockyards covering an area of 17acres were laidout. During the period of maximumoutput, these yards were equipped with thirty-four Winget block machines, eleven mixers, and six portableen,' Ulnes. The total number of blocks manufactured exceeded 14 millions, the mnximum output being reached dwing the week ending 13th September, 1917, when 81,000 blocks were made at an average cost of 0.58 of an honr's labour per block. An output of 20 pulls per hour per machine was aimed at, and this was reached and exceeded in the case of the smaller blocks, but the heavy blocks, which formed a highproportion of the blocks manufactured,somewhat reduced this over the entire output. With German prisoners of war, the average number of pulls was 17 per hour during the summer rr.onths and somewhat less dnring thewinter. Later, when the German prisoners had been with- drawnand soldiers of lowmedical category wereemployed, the output fell to 14.65 pulls per hour. BEocks.-Two classes of blocks weremanufactured, consisting respectively of an aggregate of sand and crushed flints, and sand and clinker, the proportion of the former being 1-2-3 and the latter 1-1b-23. Thisconcrete stood well, andthough the panels of the walls of the huts are but 23 inchesthick, it was found that no necessity arosefor plastering, a wash of waterproofcompodtion being all that was required to ensure dryness.

Cost.-The average cost of the materials was 6 9d. per cubic foot and of labour 6 03d. per cubic foot. Table I describes and gives the cost of the blocks manufactured.

TABLEI.-AVEUQE CO8T OF WINGET BLOCKS,MAY, 1916, TO NOVEMBER,1918.

Volume lumber Material. Labour. Potal Cost in of Cost per Cost per per Block Cubic Blocks Block at Block at at 12'93d. per ?.Sod. per 5.03d. per per Cubic Feet. Pull. ubic Foot ubio Boot l. Foot. -- Inches. Pence. Pence, Pence. Panelslab . 1 28a by 23 0.34 3 2.346 2.05 4.396 +?o. ..1 142 ,, 2k 0.17 6 1.173 1.025 2.198 Partitionslab. 1 32 ,, 43 0.75 2 5.175 4.522 9.697 *.do. . . , 16 ,, 4+ 0.39 4 2.622 2.291 4.913

Pier block . ~ 32 ,, 9 1.26 1 8.694 7.597 16.291 4 do. .. 16 ,, 9 0'63 a 4.347 3.798 8.145 Quoins . . , 16 ,, 32 1.50 1 10.35 9.045 19.395 Singleflue . 1 16 ,, 16 0.90 2 6.21 5.427 11.637 Double ,, 1.80 1 12.42 10,854 23.274 Closers ._. 0'42 4 2.898 2.532 5'430

,f ' 9 7, 64 0.30 4 2.070 1.809 3.879 0'63 ,? ~ 9 ,) 134 2 4.347 3.798 8'145 Specialpiers . , 32 ,, 9 1.26 1 8'694 16.291 htullions . . 1 .. 0.10 8 0.690

Annlgsis of Labour.-An analysis of the labour employedgives the following ratio for the variousservices obtained :-

Unloadingcement, sand, clinker,etc...... 0.062 Gaugingand mihing ...... 0.094 Makiug and carrying out ...... 0.469 Watering ...... 0.031 Clearing from drying ground and stacking ....0.195 Loading ...... 0.125 Itepsir to sheda,machines and stacks .....0.016 Supervision L ...... --0.008 -1.000 The output from the blockyards was not used only at Richborough, but was utilized inthe construction of aerodromesand other worksundertaken by the Inland Waterways and Docks outside Ricllborough.

The drainageof the main groupof camps was carried on the water- carriage separate system. The drains, sewers, and works were not designed for dealing with surface or storm water. The works, when working to the full capacity, were designed to deal with the daily flow of 250,000 gallons from a population of 25,000 persons. Two main 9-inch sewersgravitated through Stonar, Haig and Kitchener Camps, picking up subsidiary sewers and drains in their course. These sewers discharged into a 33-inch cast-iron tank sewer, which emptied into a pump-well situated to the west of Kitchener Camp. The sewage from thepump-well was raised by meansof centrifugal pumpsand discharged into tanks atthe sewagedisposal works. Theseworks were situated well awayfrom the camp onthe left bank of theriver opposite Richborough Castle. Thepurified effluent upon leaving the works was discharged by gravitation into theRiver Stour. The sludge was disposed of byland treatment, but it was possible to deposit the sludge at sea by means of hopper barges. Sewers.-Owing to the water-logged nature of the ground, and to avoid unnecessary timbering, the sewers were kept as shallow as possible. Thestoneware pipes were of thefirst quality with Stanford patent joints to ensure thesewers being absolutely water- tight,and were provided withcast-iron ventilating columns at intervals. To avoid constructing a large underground tank or pump well, and owing to thedifficulties and expense of timbering in the water- logged ground, a 33-inch cast-iron tank sewer, 281 yards in length, with a capacity of 30,000 gallons, andcontrolled by an 18-inch penstock at the pump well, was constructed. Pump Well atrd Pump Ho?cse.-The pump well was constructed of concrete blocks, 15 inches thick, and lined with 4& inches of blue brickwork; it was 8 feet 6 inches in diameter, and 15 feet in depth. Special carewas taken to ensure that the floor of the well was absolutely water-tight. Thepumping plant consisted of two5-inch Parsons patent stereophaguspumps, actuated by 10 B.H.P. electricmotors, 220 volts, 40.5 ampkres. There was also one 5-inch stereophagus pump actuated by means of a 19 HP. oilengine, which wasused as a standbywhen the curreut wm shut off at the power station. Xach pump was constructed to pump 450 gallons of crude sewage per. minute against a total head of 31 feet, when running at a speed

of 930 rcvolutionsper nlinutr. The impellers werespecially constructed to chop up crude sewage. There were twovacuum pumps, one actuated by a 13 HP. oil engine and the other by a If HP. electric motor, used for priming t,he stereophagus pumps, the former acting as a stand-by. The sewage was pumped through an S-inch cast-iron rising main for it distance of 437 yards to the Sewage Disposal Works, where it was dischargedinto an inletchamber provided with two 15-inch penstocks which controlled the speed of the sewage passing through thevarious tanks. The sewage then passed throughthe detritus chambers, constructed in duplicate and of a total capacity of 5,000 gallons ; there were baffle walls in these chambers, and the heavier detritus was deposited here. From these chambers the sewage passed along aerating chambers into the sludge tanks. Sludge TarLls.-These tanks myere constructedin duplicate in the form of inverted cones, and the greater part of the sludge was collected here. The sewage from the sludge tankswas drawn off2 feet below the surface of the sewage and discharged into the sedimentationtanks, whichwere constructedin duplicate and had a toed capacity of 80,000 gallons. The tank effluent after passing under scum boards was allowed to overflow into the dosing chamber, from which it wasdischarged throughrevolving sprinklers on to the surface of three percolating filters. Bacteria Filters.-The filters were 70 feet in diameter and 4 feet 6 inches deep ; they were composed of hard-screened clinker graded in sizes from 3 inch at thetop of thefilter to 5 inches at the bottom, the whole resting on blue stoneware interlocking drainage tileson a &inchconcrete foundation. The filter effluent after following alongaerating channels passed through a humustank containing a number of scumboards. A largeamount of floc- culent matter or humus was collected, which was skin~medoff the surfaceand buried in the ground. The effluent passed along a 12-inch stoneware outfall pipe and was finally discharged into the river Stour at any stateof the tide up to high water ordinary tides. At high water spring tides, the tidal flaps at the outfall closed, the flow of effluent was arrested and 5owed over a weir into an open storagetank of a capacity of 50,000 gallons,which discharged automatically through a separate outlet at about half ebb tide. Sludge.-The sludgedeposited in thedetritus, sludge and sedimentationtanks was liftedto 3 feetabove ground level by means of the hydrostatic head of the liquid in the tanks; it then gravitatedalong the 9-inch sludge pipe into a sludgechannel. There were openings inthe channel through which thesludge [TEIE INST. C.E. VOL. CCX.] M

Downloaded by [ York University] on [16/09/16]. Copyright © ICE Publishing, all rights reserved. 16.2 ROBERTSON ON RICHBOROUGH MILITARY [Minutes of gravitates on to the land. The ground had been under-drained at a depth of 3 feetwith 4-inch stoneware land drains and these drainseventually discharged into the storage effluent channel. Trenches or open grips were dug in the ground of the sludge area, and the sludge was allowed to settle and then dug in.

LANDDRAINAGE. The entire area (Fig. 1, Plate 3), occupied by camps and works, waslow-lying flat land, formed of recentdeposit, protected from inundationduring high water by flood banks.The general level of the surface was about8 feet above O.D., and owing toits flatness it afforded nomeans of naturaldrainage. High water of spring tides was from 2 to 4 feet above this level. Theauthority with power toprotect these areas against inundationby salt water and the maintenance therein of a freshwater supply for agricultural purposes, isthe East Kent Sewerage Commission, under whose charge a system of open channelsand dykes has been elaborated, which, intersectingthe landin all directions,draw fresh water through sluices inthe upper reaches of the river to be impounded in the dykes. To control the discharge from these dykes during periodsof rainfall, or when at suitabletides it wasdesired to impoundfresh supplies, sluices wereprovided in thelower reaches of the river. These sluices were designed to retain the fresh water in the dykes at a fairly constant level. The result of these conditions was to maintain the plane of saturation at a high level and to hinder the dischargeof surface drainage, rendering the whole area liable to 0ood during periods of excessive rainfall, and generally to establish conditions potentially malarial, whichby thefinding of anopheline lwm weresubstantiated as active. These conditions, evil in themselves, became aggravated by the change of conditions consequent to the advent of a large population,the establishment of camps, buildingand other works. The establishment of a system of open drains to ensureso far aspossible good surface drainage became imperative. In designing the drainage system chief the objects aimedat were:- 1. Utilizing so far as possible theexisting channels, all of which required clearing and re-grading. 2. A circulatorysystem of drawingfrom the higher reaches and discharging into the lower reaches, so as to permit of sluicing, the inclination of the channels being very flat.

3. A maximum number of outfalls, so as to ensure quick discharge during periods of rainfall or sluicing. 4. Arrangement of sluices to exclude water and permit of the dykes standing dry, so as to reduce the level of tho plane of saturation and in the eventof rainfall to provide reser- voirs for the surface off-flow. The system further aimed at the preservation of two zones, the camp zone and the outerzone. The dykes in the formerwere capable of being maintained dry and flushed ; in the latter zone, water had to be maintained in thedykes for agricultural purposes, butit was so controlled that it could be discharged regularly,the dykesflushed and fresh water let in, thus ensuring an improvement in the sanitary conditions. Thegradient of themain channel along the west side of the Sandwich-Ramsgate Road was 1 in 1,500, its average depth being 5 feet. The fact that the North Lake was situated in the vicinity of the camps and works, the water level of which can be maintained constantly about O.D., made feasible the provision of an outfall permanently open. The discharge from this outfall, which was on the east side of the Sandwich-Ramsgate Road, was carried to the lake through a concrete ovd sewer 1 foot 8 inches by 2 feet 6 inches, 435 feet long. In additionto the construction of themain system of surface drainage, much was done to improve the drainage and to prevent water-logging by raising the surface in camps and works, by filling up disused channels and depressions, and clearing all dykes of mud and weeds, etc. On the completion of these works, the improvement in the state of the .camps was marked, and in the summer of 1918, mosquitoes, formerly a pest in summer, were almost non-existent.

INPROYEMENTOF APPROACII CHANNEL, FORMATION OF THE POOL AND BARQEBASIN. Site of Wharves, etc.-The wharves,berths, jetties, slipways, building slips, etc., forming the new port extended along the left bank of the river Stour for a distance of about 3 miles up-stream from the pointwhere, entering the estuary,it flows through Pegwell Bay. This point is very clearly demarcated by the presence on the right bank of a gravel and sand beach known as Shellness, which forms the south-cast littoralof Pegwell Bay. M2

Iiiver Stow. ----Theriver 1~1,s its source near JPI~III,alwllt, 8 miles east of Maidstone, whence, flowing eastwards by Ashford andCanterbury and through the marsh lands, now formingthe western and southern boundariesof the Islandof Thmet, it debouches to sea through it8 estuary in Pegwell Bay, about 2 miles south of llamsgate. The length of the river, from its source to its mouth, is abo11t 49 miles. The catchlnent area, the ~E-flowof whichpasses to the river Stour, extends to 320 square miles. In its upper reaches the river maintains a fairly direct course, but whenpassing through recent alluvial deposits in its lower reaches it isremarkably tortuous. The existence of a great loop, upon which the town of Sandwich is situated, is noteworthy, the width of the neck of the loop, measured from centre of stream to centre of stream, is only 700 feet, the length of the loop measured between the same points following the course of theriver being 63 miles. The formation of this loop appears to be due to an accretion of a, shingle beach depositedunder the influence of a promontory of what was once the south coast line of the Island of Thanet. General Cause of Accretion-The arrestand accretion of sand and shingle moving along foreshores is caused by the existence of obstructionstothe free movement of thelittoral currents. Obstructions may either take the form of promontories or embay- ments in the configuration of the coast line. Either of these will arrest the currents, and, by theformation of waves, produce the force by which sand and silt is disturbed and transported. Elecation of Estuury.-Such an obstruction to thefree movement of coastaltravel was, andis, to be found in the channel dividingthe Island of Thanetfrom the mainland. The accretion of alluvial and coastal travel deposited in the embayment during longages now passes the lower reachesand estuary of the river Stour, which, as its course elongatedthrough an ever-increasing coastal accumulation, automatically carried forward the limits of its tidaland navigable reach. This resulted in the decay of its port and its re-establishmentwithin a navigablereach. Such ports abandoned in prehistoric Roman and recent times are to be found along the river at Stourmouth,Richborough, and Sandwich, now recreated inthe new Port of Richboroughto help to meet the exigencies of a great War. As the causes which led to the silting LIP of the channel between the Island of Thanet and the mainland continue, the deposition of silt in the still partially-filled embayment of Pegwell Bay proceeds,

Downloaded by [ York University] on [16/09/16]. Copyright © ICE Publishing, all rights reserved. Proceedings.] TRANSPORTATION DEPOT. 165 resulting in the formation of a broad stret,ch of mud flats and low marsh lands in which are located the approach channel, pool, and barge basin, giving access from the sea to the wharves and berths of the new port. The elevation of the mud flats and marshes beingsuch that, where not protected by flood banks, they are submerged at high-water and so constantly subject to wave action, together with the absence of any stability in so recent a formation, results in the production of silt, which is carried upstream on the flood tide and deposited at slack mater, or bywave action transported inshore. These conditions also prevent the river from followinga permanent course and leave it uncontrolled to find such a course as circumstances from time to time demand. Pegwell Bay is bounded on the south by Sandwich Flats, on the west bp the coastal and alluvial accumulations which now fill what was the channel dividing the Island of Thanet from the mainland, and on the north by the chalk cliffs which form the coast as far :LS the North Foreland. The Bay is therefore open to the sea on the east and during high-water from the south-east. The level of thesea bottom in the Ramsgate Chaxlnel, lying immediatelyto the east of theBay, is 23 feet below O.D., from which the hottom rises within a distance of 3 mileto low-water level, namely, 6 feet below O.D., from where it rises gently through the 13ay to the coast line to an elevation of 8 feet above O.D., the width of the Bay exposed at low-water being about 18 miles. Tides.-The range of average spring tides at Ramsgate Harbour is 15 feet (from - 6 to $- 9 O.D.), that of neap tides being 8 feet ( - 2 to + 6 O.D.). At the point where the river enters its estuary, which is also the site uponwhich the train ferry steamer berth is located, the r;mge of average spring tides, previous to the improvement of the channel, was 10.5 feet ( - 2.5 to + 8 O.D.), the range of neap tides being 8 feet ( - 2 to + 6 0.13.). At the timeof high-water at this point, the toe of the tidal wave justreaches Grove Ferry, a distance of 15 milesupstream. The whole of this wzve, IIO-KHT~P, is not tidal water, and it is probable, indeed, that salinometertests woulddisclose no salt water at :L distance above 8 miles fromthe commencement of theestuary, except during especially high tides. Tidul Cu~re7ct.u.-The filling of the estuary during the early part of the flood is performed by the North Sea tide which sets around llnmsgate Pier to ancl across the debouchrnent of the Stour. About 2& hours before high-water the English Channel tide pre-

Downloaded by [ York University] on [16/09/16]. Copyright © ICE Publishing, all rights reserved. 166 ROBERTSON ON RICIIBOEOUGH MILITARY [hfinutes Of dominatesand the estuary is filled fromthe south. There is no perceptible draught of flood tide to the estuary at any position or at any time of flood tide. The only upstream flood current in the outer portion of the estuary is along the threads of the extreme low-water channel, and at later stages of the tide in the confined channel above Shellness. A remarkableand constant feature of the ocean current in Ramsgate Channel is its direction approximately north-east during a period 2 hoursbefore to 2 hoursafter high-water. The time occupied in a completechange from south by west on the early flood tide to north by eastin the late half, varies according to wind and moon’s age. OnOctober 20th, 1917, theturn occupied 90 minutes, and on 16th November only 15 minutes. The reasons of this remarkable feature are due to the varying predominance of theNorth Sea and Channel currents. It is not noticeable north of Korth Foreland or south of Deal, and in a sca- ward direction it does not appear to extend to theGull Lightship. This current sets over lines fairly parallel to a line drawn from . DangerBuoy to a pointabout 200 yardsseaward of Ramsgate Harbourentrance. The inner portion of thecurrent skirts the foreshore over a length of about 2,000 yards west of the Wcstern Pier; it strikes this pier about midway from the end and shoots across the entrance with R velocity exceeding 29 miles per hour. Siltage.-Along theforeshore between the train ferry steam berth and the signal station atPegwell Bay there are unmistakable signs of accretionin varying depths. This is confirmed bythe disappearance of a parallel series of small stream beds which run from near high-water mark to the channel, now silted up, and also by a recent growth of samphire along this part of the foreshore. Beyond a linebetween Shellness and Pegwellvillage the foreshore, open to all winds from north-east to south, is clean, ,as is also theforeshore from Deal to Shellness which opento unobstructed seas and tides. Thecontour lines of theoutlying shoals are very irregular, indicating great mobility. Evidence also exists showing that during easterly gales deposits of as much as 4 feet in depth are thrown up on the eastern sideof Ramsgate Harbour entrance. Inspection of the topography of the foreshore at Shellness as recorded over a period of 13 years indicates change in contour,only to be accounted for by the accretionof coastal travel due towave action. Thebanks of theriver for a distance of 15 milesabove the commencement of the estuary show practically no sign of erosion; on the other band, all trouble experienced through the land sluices

being opened arises from the accumulationof light material brought up in suspension by highflood tides. It is, therefore, clear that the cause of siltage is wave action on the banks of the exposed portion of the estuary. Thatthe quantity of silttransported on the flood tideand deposited at slack water is considerable, is shown by the rate at whichaccumulations were deposited inthe length of theriver channel abandoned on the completion of the cut forming the barge basin.The deposits averaged nearly 6 feet in depth, the rate of deposit being 1* 37 inch per week. ~Tkfoccrne~~tof Cltnnnel in Esfuary.-From inspection of maps of the estuary of the river dating from 1775, it appears that the tendency of the river since that date has been to increase its length by the formation of great bends and constant movement of its point of debouchment at low-water northwards. Observations show that the forces tending to make the channel of the river throughout its estuary more tortuous are still active, nor can any evidencebe found to show that avulsion follows theformation of acutebends, so thatonly by artificialmeans canthe channel of theriver be maintainedsufficiently direct for navigation,

DESCRIPTIONOF CRAFT UTILIZINQ THE PORT. The waterways and wharves were designedfor the accommodation of two classes of craft, and the tugs required for their movement. These were :- (l) The train ferry steamers. (2) Port discharge(P.D.) barges of 1,000 tons, and Across- channel (A.C.) barges of 200 tons capacity. The draught of the port discharge and the across-channel barges fully laden was 11 feet 2 inches, and 5 feet 9 inches respectively, their lengths over all being 187 and 128 feet.

CONDITIONSAFFECTIKG THE ALIGNMESTAND DIMENSIONSOF CHANNEL. Thealignment of thechannel relative to currents, safety of approach, siltage and navigation, was the subject of constant study, based uponexperience andobservation accumulated during the period the port was in process of construction. As the earlycompletion of the port was of paramount importance, there was little or no time for extensive preliminary study of the project, resulting in the modifiwtiop of the schepe from time to

timein the light of the volume of traffic to be dealtwith and experience gained and considered. It was fromthe first evident that the unstable, tortuous, and shodynature of thechannel through the estuary rendered it totally unfit for navigation. The alignment of the channel, Fig. 2, took four definite locations, that in theupper half of theestunry being, however,common to each successive proposition. Fig. 2.

l .%AL. Y&'?mdr -1,Uds. f, + .M& RIVERSTOUR IMPROVEMENT: ALTERNATIVE SCHEMES.

First dZipment.-The first proposd aimed at the provision of a straight channel, the sectional area and bed level being designed to follow that of the existing channel and aligned to follow the set of flood and ebb tide currents as then apprehended.

TABLEII.--ESTIYATED QUAXTITIES TO BE DRGUCEII.

Alignment. QI'antity. Alignment. 1 Cnbic Yiar(1s. I ~clnnrlis,

~~ ~ ~~ KO. 1 to-7 ft. 0.n...... No. 1 to-l2 ft. 5 in. 0.n...... No. 2 ...... No. 3 ...... 1,521,057 pool and No. :: (BM amended) ......

The quantity to be dredged in the formation of this channel WRS 145,439 cubic yards. Work had just been commenced on this scheme when the establishment of a service of trainferry steamers was decided upon, which it was considered necessitated a channel having a depth of 10 feetat low water and a width of 200 feet. Thischange increased the quantity to be dredgedto 712,000 cubic yards. Scconcl Ali!/)rmcnt.-Later, owing tothe urgency for the completion of the channel, and as it was found that the outer length of the existing channel would with certain improvements meet all the requirements for navigation, a second alignment was adopted, resulting in the reduction of the quantity to be dredged by 101,000 cubic yards (Table 11). Third AZignmetrt.-In view, however, of the establishment of the train ferry steamerservice, a hydrographical survey of Pegwell Bay, with observations of currents, was undertaken, the result of which let1 tothe roconsiderntion of thealignment to be followed as investigation shon-ed tlyat :- (i) The line of the outer channel as originally proposedwas dangerously near the western Ramsgate foreshore. (ii) The line of approach to it was in very broken water. (iii.) The set of both flood and ebb tides is at an unfavourable angle both for the maintenance and the navigation of the alignment previously decided upon. These conclusions led to t.he adoption of a third alignment, the R.pproximate quantity to be dredged for the complete scheme being 843,700 cubic yards, thus providinga depth of 10 feet at low water, so as to permit the passage of ferry steamers during a considerable period of the tidal range. Owing, however, tothe draught of theonly suitable dredgers which could be obtained to work in so exposed a situation, and as low water. in the outer portion of the estuary is G feet below O.D., it was obvious that it would be necessary to dredge to such a level as would increase thequantity to be dredged by 517,800cubic yards. Fourth AZinnmenf.-Meanwhile suchprogress had been made in theconstruction of berthsand wharves and the dredging of the inner length of the channel that the ferry and barge service had been establishedand considerable experiencehad been gained as to the volume of traffic which conld be delivered to and dealt with ;it t,he port.

Downloaded by [ York University] on [16/09/16]. Copyright © ICE Publishing, all rights reserved. 170 ROBERTSON ON RICHBOROUGH MILITARY [Minutes of On consideration of this information, and in viewing the effect which the improvements introduced in the upper reaches had had on the lower reaches, it was clear that all the requirements of traffic and navigation could be met by adopting the channel consisting of the newly-formed upper reach and the lower channel practically as it then existed, and the fourth alignment was under the circumstances decided upon.

THE POOL. The pool, extendingfrom the commencement of thechannel upstream to the barge basin, is 2,900 feet long, the greatest n-idth being 500 feet, andit provides a turning basin for the ferry steamers andaccommodation for barges laden or lightoutside the barge basin, where they hamper the movement of barges along the wharf front when not actually required.

THE BARGE BASIN. The location and formationof the barge basin constituted part of the wharf project. It was formed originally to a width of 100 feet with 5 feet of water at L.W.O.S.T., and is about 2,500 feet long.

Later,owing to the increase ' of theequipment for handling traffic, the basin was widened to 300 feet, measured at H.W.O.S.T.

GEOLOGT. Thesea bottom along the west side of theRamsgate channel, from a distance of about g of a mile eastwards of the low-water mark in Pegwell Bay, is hard and consists of green shale ; on "p- proaching the mouth of the river at low tide this formationclranges tothe chalk of which the cliffs alongthe north littoral of the bay form part. Passing inland the shale is covered with a bed of hard sand and clay, the latter often honeycombed by innumerable shell-casts. This bed is in turn overlain with gradations of the fine mudand sand formingthe flats of Pegwell Bay. Along a line followingapproximately the river channel through the bay, the shale dips and isreplaced by a bed of hard green marl. Quantities.-Table I11 (p. 171) shows thequantities calculated from cross sections as actually dredged. Dredging Plant.-In view of the urgency for the completion of tEJe chnnnel, these quantitJieswere formidable and obviously implied

TABLE111.

Excavated by Total Situation. Cubic Yards. Land ~---Appliances,‘1 -- Barge basin ...... 174,465 33,740 208,205 Wideningbarge basin . . . . . 199,590 I 24,000 223,590 Pool . . . . . , . . . . 677,357 677 ,357 Approachchannel (Scheme No. 4) . . 527,623 1 :: 327 ,623 1 Abandonedalignment (Schemes 2and 3a) 149,615 1 .. 149,615 -- -- 1,528,6505f,740 I l, 586,390 the employment of a large fleet of dredgers, hoppers, tugs and other craft. Atthe period of greatestactivity, eight dredgers, two steam hoppers, seventeen hoppers and dumb barges, seven tugs, and other craft were employed. The suction dredgers “Cruachan”and “Riparian” were employedin discharging the contents of dumb barges to reclamation areas. One and sometimes two bucket dredgers were employed on maintenance work. This fleet dredged, discharged at sea or to reclamation areas on an average 14,000 cubic yards hopper measurement daily. The total hoppermeasurement quantity discharged in completing the project in its final form, excluding all maintenance dredging and excavation by land appliances was 3,532,979 cubic yards. In considering these figures it must be recollected that work was carriedout under somewhat unusual conditions, and by military working parties. The exposed situation of the work, air raids, and the difficulty of obtaining suitable craft in good repair led to delays which could ill be afforded. Of the total quantitydredged 2,814,547 cubic yards were pumped ashoretoreclamation areas and 1,132,722 cubicyards were dumped at sea. These quantities included 414,290 cubic yards, the result of maintenance dredging. Reclamation.-Threeareas, extendingin all to 235 acres,were selected for reclamation, the general ground line being 8 feet above O.D. Thedepth of fillingdecided upon was 6 feet 9 inches, bringing the surface to14.75 above O.D. In selecting these wess advantage was taken of the existing flood

protection banks to form part of the banks required to contain the discharge from the suction dredgers, thus out of a total length of 8,200 lineal yards of bank, only 5,200 had actually tobe thrown up. Area Eo. l extended to 55 acres, into which 770,000 cubic ynrds were discharged. KO.2 area, extending to 103 acres, had a capacity of 900,000 cubic yards. No. 3 area, extending to 77 acres, was able to take 847,000 cubic yards (Fig. 1, Plate 3). The banks along part of the east side of area No. 2 and at the north e:& corner of area No. 1 were protected :xgainst wave action by :L revetment of gunny hgs filled with sand and gravel. In theformation of area No. 3, the bend inthe river course, :handoned on completion of the cut forming the barge basin along thewharf, had to be closed. Duringthe period, approximately l? months,which h:Ld elqxedsince the new channel lladbeen opened and the old channel abandoned, deposits had accumulated to n, maximum depth of approximately 9 feet, the old channel always remaining open, however, and permitting n considerable volume of 1"i;I. 3.

S&. ?Z&=4OF& &Cg, p 5 10 <6 $0 +5 qOF&

BAG DAM ACROSS OLD RIVER COURSE AT RICHBOROUGH. water to pass up and down on the rise and fall of the tide. The closing of the upper end of the channel presented no difficulty and W:W efl'ectcd by tipping an ewthen bankacross it. In dlosing the lower end, provision had to be made for the free ingressand egress of tidalwater during the construction of the dam, which it was arranged would be closed on a neap tide. The tiam consisted of gunny bags filled with sand with:I, hearting of sand, and it was constructed from both banks simultaneously (E'ig. 3). In this method of closing n stream, flowing with an ever-increls- ing velocity as the channel became narrower, the protection of the bottom against SCOUT had to be ensured. This was effected in this instance by laying on the bed of the stream,for a distance of 30 feet upstreamand 55 feetdownstream, n thickapron of gunny bags filled with sand, upon which the dam was formed. Immediately on thecompletion of the dam, the endof the delivery pipe from the suction dredger wns brought up behind it, and the d:m~sc:~lrci 1111 to within 3 feet of its t,op leyel within 10 clays.

It may be recorded that, although the pressure withstood by the clam, which was built on an apron laid on :t thick recent deposit of silt, must have been very considerable, no movementwas observable. The suction dredgers ‘(Cru:tchnn” and (‘Riparian ” were used exclusively for discharging the transporters, suitable berths being constructed from-time to time in close proximity to the areas under reclamation. The “ Cruachan ” is 150 feet long, 39 feet beam, 13 feet mean depth,and drams 8 feet,and can discharge 700 cubic yardsto 1,000 cubic yardsper hour. The mud in the transporters was diluted by a jet of w:tt,er and sucked up through a pipe 21 inches in diameter by means of a rotary pump, and was forced through :I 21-inch diameter pipe, which may extend for 460 yards. The “ Riparian ” is of verysimilar dimensions, the engines indicate 900 HP. Thedredger can discharge from 800 cubic yards to 1,200 cubic yards through a 25-inch diameter pipe with 24-inch delivery pipe extending to a length of 500 yards. The effluent fromthe areas during reclamation wasdischarged through 4 feet by 4 feet sluices situated at the greatest distance from the end of the delivery pipes. Reclamation of thearea Eo. 1, requiredfor early occupation, was practically completed on 15th September, 1917, and 3 months later 2,000 yards of railway track forming the train ferry railway sidingshad been laid.On the 6th June, 1918, theerection of temporaryhangars and buildings was commenced, withrailway sidings, and by December, 1918, :L 20-foot road giving access from the main road to the train ferry berth hadbeen completed across it. No trouble was experienced in the construction of these works, and little or no inconvenience was caused from instability of the filling. Thenew banks bounding the areas, although light in section, stood well, and in some cases the outer face was soon covered with a thickgrowth of samphirewhich protected them against water and wave action. In order to make these banks as impervious as possible, turf was stripped from the site (the earth required for the banks being borrowed from the area to be reclaimed) and relaid on the base of the bank. LIGHTIKG. The approach to the river was marked in Ramsgate Channelby a steelacetylene gas and bell fairway buoy, showing a triple flash whitelight of 50 candle-powerevery 10 seconds. Theentrance to the channelwas marked by two flat-bottomed buoys, the channel being demarcated by a series of four-pile beacons, all showing flash-

Downloaded by [ York University] on [16/09/16]. Copyright © ICE Publishing, all rights reserved. 174 BOBERTSON ON RICHBOROUGH MILlTABY [Bainutm Of lightsfor 4 of a second,followed by 2 of asecond darkness, i.e., sixty flashes perminute, which was practically continuous. The lights on entering showed red on the port side and white on thestarboard. The illuminant employed wasacetylene gas, the brilliancy of the lights being 50 candle-power ; each cylinder con- tained sufficient gas to ensure lighting fora period of 6 weeks. Generally, therefore, the resultof the operations described above was to convert anunimportant, narrow, tortuous and unstable waterway into a navigable channel, and a tidal dock basin having a water area of 50 acres navigable for ships 363 feet in length and 960 tonsburden, and providing accommodation for a fleet of sufficient barges, tugs, etc., to maintain the transportation of 8,000 tons daily. Theimprovement of theriver made possible the building and erection of 194 craft of different types required for war service andthe maintenance of a very considerablefleet of barges and small craft.

COST. The total expenditure on the provision of the channel and basins amounted to 2335,476, of which amount 219,777 was incurred in the provision of the original barge basin. ‘Ananalysis of thisexpenditure shows theformation of the original barge basin cost 22.8d. per cubic yard, net amount.

TRAINFERRY BERTH. A proposal to establish a cross-channel train ferry service for the transport of militarystores between the French ports and this country was putforward towards the end of 1916,from which matured the Richborough-Calais-Dunkirk and Southampton-Dieppe train ferry project,which included the provisionof three train ferry steamers,with terminal berths at Richborough, Calais, Dunkirk, Southamptonand Dieppe, the construction of access railways, sidings, oil storage tanks, offices, etc.1 The Richborough terminal berth was located on the left bank of the river Stow at the point where it debouches to its estuary in Pegwell Bay. The approach to the berth through Pegwell Bay was by the course of theriver, which, at highwater, average spring tides has a maximumdepth of 18 feet,and at low waterspring tides 4.5 feet,The range of springtides is 13 5 feetand of

F. 0. Stanford, “The War Department Cross Channel Train Ferry.” Post, p. 20s.

TABLEIV.-DETAILS OF COST OF DREDQINGTHE POOL AND CEIANXEL.

Cost per Cu. Yd. Hopper. _l___l_ -- -I_ iL S Pence.

Supervision ...... ~ 4,996 0.35 Hire of craft and plant...... 96,672 6'60 Salaries of civiliaus ...... 10,131 0.70 Military labour ...... 112,504 7.65 Coal and water ...... 22,282 1.25 Stores ...... 37,295 2.55 Repairs :- Material ...... l 34,018 2.30 Labour ...... 17,578 1.10 ___- -- Total ..... 335,476l 22'50 l Dredgingonly ...... 7.20 Disposal of dredgings ...... 6.80 Generalcharges ...... 3.30 Dischargingon to reclamationareas ...... 5.20 22.50

l Includes 25,103, the coat of excavation by land appliances.

neaptides 9% feet.The site is sheltered from wavesby the protection of Shellness Point. The berths for the reception of the train ferry steamers had to follow closely their form, so as to permit of the vessel being docked securely and firmly against the access track, and permit of the least possible movement during loading. A ramp or communicationbridge, adjustable between definite working gradients, actuated by lifting machinery was required to carry continuous railway tracks from the shore to the railway platforms on the ferry steamers. Thelong jetty also provided support for oil and water supply appliances and formed an access to the vessel. Theberth had to be so located andthe approachchannel so designed that the steamer, if single-ended, could on arrival swing safely before berthing. This may require the provision of dolphins outside theberth along the approach channel if thefairway is restricted. Bores disclosed the Shbtn in which theberth was to becon-

structed,to consist of sandxnd silt tu :L depth of 35 fcrt fronl the surface, after which llard green mar1 was met. Appoacah Clmnnel.-It was fromthe first evident tlmt the situation of thissite necessitated the formation of anapproach channel and turningbasin, the dredging of whichformed an important pwt of theproject. The width of thechannel at the entrance OF the berth, measured at H.W.O.S.T., is about 500 feet, with a depth of 10 feet below L.W.O.S.T. The cohstruction of the berth fell into six distinct divisions :- l. The wharves forming the berth. 2. The communication bridge or ramp connecting the railway track on the steamer with thedock railway system. 3. The machinery and its supports for lifting and lowering the bridge. 4. Excavation of the berth. 5. Railways and sidings, G. Oil fuel tanks and delivery. Berth Wharuex.-The level to which it was decided to excavate the floor was 16.5 feet below O.D. which, allowingfor a L.W.O.S.T. of - 4.5 with the maximum drnftof 10 feet, gave2 feet for clearance below the keel. The average ground level at the siteof the berth being 8 feet, it was necessary to surround the berth with some form of dock wall (Fig. 4, Plate 1). The dock orretaining wall formingthe berth consists of the “UniversalJoist” pattern of steelsheet piling. The joists are l5 inches by 5 inches and weigh 39.5 lbs. per foot run, the sectional area being 11-65 square inches. The weight of the clutch per foot run is 15-5 h., the sectional area being 4.55 square inches perfoot.

SECTION OF STEEL SHEET PILING. The total length of the wall is 1,060 feet. The top level of the sheet piling is 13.5 feet above O.D. on the north side, (being one footabove the level of thehighest anticipated spring tide), and 9-50 feet on the south side. The piles were driven ato hard bottom, thelevel of which is 22 - 30 to 26.50 feet below O.D. The pileswere drivenby 2-ton B.S.P. semi-automaticdirect actingsteam piling hammers and to a general specification of driving to refusal, or eight blows per inch.

The recess in which theadjustable bridge or approach ramp works is about 80 feet long by 36 feet 6 inches wide, the side walls being formed by steel sheet piling anchored to concrete blocks. The abutment supporting the land end of thebridge, and carried on twenty-four 12-inch piles, was constructed in concrete, the width of the base underthe bearings of thegirders being 13 feet.The maximumpressure on the bottom of theconcrete is 3 tonsper squarefoot, the load carriedby each pile, assuming no load on ground, is 45 tons. To take the horizontal pull of 25 tons, which may be transmitted to the abutment from the bridge, the abutment was anchored to a concrete block carried by three piles, 72 feet back from the centre of the abutment bya 2&-inch diameter steel rod (Fig. 5, Plate 3). The timber wharf, forming this berth, lay within the sheet pile wall against which it butts, thereby giving it considerable lateral stability to resist the impact which was sustained by the structure during the berthing of vessels. The objects at which the design aims were :- (i) To provide a safe berth for the vessel. (ii) To permit of easy and expeditious berthing. (iii)To afford means of safe andquick egress and ingress of rolling btock from and to the railway platform vessel. on the The deck, the level of which is 22 feet above O.D., was provided with bollards, to which were secured the breast moorings. The site was exposed from the north-east and protection was obtained by so laying out the berth that the vessel when berthed lay to the lee of the wharf forming the long arm of the berth. The wharf forming the long arm of the berth followed the usual form of wharf design, somewhat heavily tied and strutted at the pierhead (Fig. 6, Plate 3). The piles were driven to refusal, the level of the shoes varying from 19 to 30 feet below O.D. Thefactors inthe designintroduced to ensure the easy and expeditious berthing of the vessel lay in so forming the berth that the vessel was guided in and held secure in such a position as to make possible an exact junction between the railway tracks on the vessel andthose on the bridge or ramp leading from the land railway tracks. This was effected byslightly splaying the endof the wharf forming the long arm of the berth, and theprovision of a short arm slightly splayed, both leading to the root of the berth, which was curved to follow theform of thestern of the vessel, aroundwhich were [THE INST, C,E, YO~,CCX.J N

Downloaded by [ York University] on [16/09/16]. Copyright © ICE Publishing, all rights reserved. 178 ROBERTSON ON RICIIBOROUGH MILITARY [Minutes of arranged a system of fender piles, against which the vessel is drawn tightly. To control thevessel during berthing andto secure her in her exact position for loading and unloading, two mainbollards were provided :stern of the vessel from which hawsers were led round faideads on the vessel to the after steam capstans, which pulling on the hawsers bringthe vessel homeagainst the root of theberth. The breast mooringswere made fast to the bollards on thelong and short arms of the berth. The design of the root of the berth and the short arm followed closely the general type design of the long arm, modified to special requirements as shown on the accompanying plan (Fig. 7, Plate 3). The deck consisted of 9 inches by 3 inches planking, access being ohtained by stairways on either arm, the mllole being protected wit’ll a light wooden handrail, in the line of which posts for carrying the light brackets were provided. At the extreme end of the short arm ~tsignal post was provided for the exhibition of flags by day and lights by night. A shelter containing an automatic tide recorder was provided at the pier head of the short arm supported on the middle horizontal bracing. Access to the railway platform on the vessel was gained over the bridgeor ramp, the free end of which bears on two“elephant’s feet”resting on seats on the vessel. As pointedout previously the vessel was held in position by stern and breastmoorings, but the bridge was further secured to thevessel during loading and unloading by a heavy forged steel centring pin, designed to take a horizontal pull of 25 tons, which, projectingfrom the deck of the vessel, engages in an annular rung located in the centre and projecting beyond tlle floor of the bridge between the ‘[elephant’s feet.” The design of the berth therefore ensured that when berthed, the vessel was held in such a position thatthe bridge when lowered and engaged with the vessel, made the rnilway tr:tclrs on tile bridge fall into correct alignment with the tracks on the railway platform on the vessel, the connection being effected by hinged spliced joints 23 L- inches long. The excavAtion of the berth was doneby grab and ladder bucket dredgers. To guard againstaccidents which might occur owing to the inability of the vessel to disengage from the bridge if the fouling limits of the movingparts were exceeded, the vesbelwl:en not actuallyloading or unloading was drawnnot less than 10 feet forward, well clear of the free end of the bridge. Bfect OIP Tides due to &nprore?~zentof’ Cl~arznel.-~t has been

Downloaded by [ York University] on [16/09/16]. Copyright © ICE Publishing, all rights reserved. Proceeding$.] TRBNSPORTATIOX DEPOT. 179 recorded above that under natural conditions the range of tides at the siteof the berth previous to the commencementof the formation of the approach channeland turning basinwa,s 10.5 feet H.W.O.S.T. As, however, it was known that H.W.O.S.T. at Ramsgate, 3 miles north of the ferry berth, is9 feet above O.D., and L.W.O.S.T. 6 feet below O.D., it wasrecognized that the effect of the formation of thechannel and other improvements would be toincrease H.W.O.S.T. andto lower L.W.O.S.T., which forthe 6 months ending31st August, 1918, averaged 8 feet 11 inches above O.D. and 4 feet G inches below O.D. respectively, the average levels for each of the 6 mont,hs for spring and neap tides being as shown,on Table V.

TABLEV.-AVERAGE HEIGHTSOF HIGE AND Low WATER AT TRAINFERRY BERTHFOR 6 XONTHS EXDING AUGUST,1918.

~ Spring Tides. 11 Neap tides. I Month. I /j 5ronth. 1- I H.W.L. ~ L.1V.L i U.W.L. L.W.L. .Above O.D. Below 0.D Above O.D. Below O.D. -p-'--8---i- -p-'--8---i- -

1 Ft. Ins. ~ Ft. Ins. 1 1 Ft. Ins. Ft. Ins. March . . . ' 8 tif ~ 4 6 Narch . . . 1 5 7 38 April , . . . 9 0 ' 4 6 !( April . . . ' 6 2% 2 10

May . . . . S 7 ' 4 6; ~~ Xay. . . . ~ 6 1 39 i June . . . 8 11 6 i June . . . ' 6 6 3 sg . ~ 4 July . . . . 9 1 , 4 6 '1 July . . ., 6 64 3 Q August 9 4 ' August. . . 2 . . . ~ 4 62 6 3 ?l ~______~_-. l- l -- 3 54

Adjustable Brid!le Connecting Shore Tracks and Tracks on Vessel.- The span of the bridge giving access from the land tracks to the railway ferry steamer is 100 feet between centres of pivot bearers or 102 feet 6 inchesover all. T!he bridgecarried a double track, 11 feet G-inch centres, the width of the bridge between centres of girders being 2.5 feet 11 inches. The depth of the main girder over backs of channels forming the webs of the top and bottom flanges is 13 feet 3 inches (Fig. 8, Plate 4). To takethe oscillating movement, which wascommunicated from the steamer toDhe bridge during loading or unloading, or from other causes, the anatomy and the details of design of the bridge are notwithout interest, but before, however,passing tothese features the general weightsancl loads sustained by spans of 120 feet, 100 feet, and 80 feet of this type may be tabulated (Table VI), NZ

NO^ mmw I

N o Fn m ww

m m

ica

Nails Girders.-The flanges at aicentral section consisted of two plates, 2 feet 0 inchesby & inch and two l5 inchesby 4 inches. B.S. Channel KO. 27 suitablystiffened about every 3 feetby diaphragms(Fig. 9, Plate 4). Thediagonals consisted E of channels, the vertical posts of plates and angles. The ends of cross girders were introduced between theplates forming the vertical posts betweellwhich they move freelyon n 4-inchpin point (Fiy. 10). The stifTening-pl:~teson the sitle of thevertical posts were not riveted until the cross girders were in their places. From the bottomof main posts, 1, 3, 5, and 7, cleat platesand angles were fixed which carry the main lower horizontal brxing suspended from 3-inch pins (Figs. 11, Plate 4). Therivets required in joining thestiffening plates at the pin joints mere all countersunk, and the sides of the cross girdersand cross struts of the lower horizontalbracing moved freely at thesebearings, thepins being lubri- catedthrough Stauffer lubricators(Fig. 12, I'lste 4). Cross Girders. - Th e length of the cross girders betweencentres of pin ADJUSTMENT OE CROSS GIRDER bearings is 25 feet 11 inches *NO GIRDER POST. andthey were formed of rolled steel joists, 24 inches by 79 inches by 100 lbs. per foot, with <-inch flanged p1:ttes. The pin joints formed with the vertical posts of the main girder bear evenly on check plates on the plates of the posts (Fig. 13, Plate 4). The cross girders at the land and ship ends were slightlymodified to suit, the special requirements of these positions. LongitudinalGirders and Rails.-These consist of rolIed steel joists, 12 inches by 6 inches by 44 lbs. per foot,spaced 4 feet 11 inches

Downloaded by [ York University] on [16/09/16]. Copyright © ICE Publishing, all rights reserved. 183 ROBXRTSOK Oh' IZICfiBOEOUGH JITLITABY [.JIinUlco of centres, to give a space of 11 feet G inches betveen tracks which run throughthe entire length of thebridge supported on the cross girders as shewn. They were tied to each other by l-inch dimxeter bolts and strutted diagonally and horizontally by 3-inch by 3-inch by $-inch angles so as to mainhain an accurategauge, the outer girders being stiffenedand fixcc1 to thecross girders by gusset knees. The floor corresponding to the 6-foot wa.y consists of -;',,-inch plate resting on the top of the cross girders. The rail consists of a $-inch by 23-inch steel bar, the edges being

_.__._.C-.___.-- -

.- -. - . -. -. - . -

LOWER HORIZONTAL BRAC~NG.

rounded to $-inch radius which was fastened to the topof the longi- tudinal girders by 2-inch diameter countcrsunk bolts spced 3 feet 6 inches centres. Iozuer Horizontal Braciy.--Tlle lower horizontal bracing was introduced at the bottom of tlle alternate vertical posts by pin joints, so as to adapt itself to the transverse movements of thebridge, andconsisted of fourmain braced cross strut,s connectedlongi- tudinally by 10-inch by 35-inch channels and braced diagonally by angles 5 inches by 5 inches by 4 inch (Fig. 24).

Beariug at Land Eid qf Bridge and Ball Picot at Stern of Ship- Details of the connections between the adjustable bridge and the TrainFerry already referred to are shown in Fig. 15, Plate 4. The hinged pivots, Fig.16, for securing the bridge to the land were of cast steel, witha tensile strength of 26 to 35 tons per square inch, with an elongation of 20 per cent. in not less than 2 inches. The minimum dead and live lo:lds coming on this bearing were 30 tons and 80 tons respectively. The pivots consisted of a double-eyed brackst resting on the abutment and a bearing fixed to each main girder working on a 7-inch diametersteel pin shouldered to 8 inches at centre,between the jaws of thebracket. To take the horizontal stresses two 23-inch diameteranchor bolts were secured ta each bracketby Zj-inch diameterpins secured by&inch split pins. The bolts passed through the masonry to the back of the abutment at an angle of 25degrees so as to take hold of asgreat a mass of masonryas possible. Lubricating channels were formed in the bearing surfaces in the jaws of the brackets and oilgrooves in the curved surface of the bearings, the moving parts being protected by :-inch plate covers. On the steamer end of each main girder a ball-bearing of cast steel was provided consisting of a hemispherical pivot which rested on the steamer and a cupped bracket fixed to the girder, the hemispherical pivot being secured, but not rigidly, to the cupped bracket (Figs. 17, Plate 4.) Machinery Tozoer.-The tower consisted of twomain columns 42 feet high, 5 feet 6 inches square, spaced 36 feet 6 inches centres. The columnswere built up of i7,-inch plates and 4-inch by 4-inch by 3-inch angles, stiffened horizontally about every 5 feet 4 inches by 3$-inoh by3&-incli by $-inch angles. In the columns move the counterweights for supporting which timber rests and guides were fixed (Figs. 18 and 19, Plate 4.) The inner sides of the columns, towards the bridge, were fitted with guides and rubbers to take the suspension beam and sides of the main girder. Each column was strutted with a raking strut consisting of two channels 15 inches by 4 inches by 42 Ibs. crossbraced (Fig. 20, Plate 4.) Theheight of the column provided for a movement of the communication bridge through a range of 6 feet 10 inches. 11Zachinery.-The liftingmachinery which was carriedon cross girders 4 feet deep resting on the columns is housedin a light iron structure,the necessary floor areabeing supported by gussets

projecting from the girders. The girders also provitlell support for the sheaves over which the cables pass. Access to the machinery was gained by a ladder Rttnched to the back strut. The lifting winch whichoccupied an areaof about 13 feet 4 inches by 8 feet 3 inches was operated by a 20-B.€€P. alternating-current 220-voltmotor, auxiliary hand clutches were also provided. The gearing was designed to work in conjunction with count,erweights. To provide for holding the hridge duringthe :)(ljnstment of ~'oprs, or when the bridge w~ nncler repair, 45-inch di:t.nLeter hnspmsion linkswere provided, which hang from the nmchinwy girdev, tlle free ends of which,when in use, wereconnectetl by :L pin to the suspension beam of the bridge atX ant1 Y. To fwilititte the connection being made, s~nall permanent platforms were attached to the columns, access to them being gainetl by 1:wlders leading from the machinery platform. Two wireropes,A and B, of 5-inch circumference(Fig.l8), led from each of the counterweights in the columnsover the sheaves G and H to the drum M, round which they take about 2a-22 turns, from whichthey pass to the link sheave D, whena load of 124 tons comes on theeight falls of rope.The ropes passed over the con- veyzncedrum %; tothe adjusting ge:w fixed to the girder at F, which is rotated by a system of gearing operated by hand from the machinery room. The bridge wils connected to the link sheaveby 111eansof two suspensionlinks, I and J, which move in pin joints fixed to the t80p flange of the girder, the upper ends of the links hanging from the suspensiongirders XY, which in t8urn was connected to the link sheave by the yoke XKY. Railmay Sidings.-For the accommodation of the railway wagons received fcr transmission by the ferry, foursidings, each of suEcient length to hold fifty-four wagons, with engine and brake were provided. Fromthese sidings an access line led toa grid of sidings located close up to the ferry berth. These sidings were laid in two gt-oups of three cachconverging into two main tracks over the communication bridge. In these sidings were marshalled the wagons awaiting transmission. Oil Tanks.-The oil tanksfor the storage of oilfuel required bythe ferry steamers were placed about 800 feetsouth of the berth. There were four tanks, each 35 feet in diameter and 20 feet high, with a capacity of 120,000 gallons. The oil was delivered in tankwagons on a siding at the oil tanks, and it is discharged from the tanks into a sump 25 feet by 3 feet

by 6 feet deep, from which it passes through a 6-inch diameter &eel pipe to the pumpwhich delivers it to the tanks. The two pumps, right and left hand, with11 inches by 12$ inches vertical triple ram, were driven by a 34 HP. 220-volt motor, and were each capable of delivering 100 tons of oil per hour against a pressure of 70 lbs. per square inch. The foundations for the tanks consisted of a rammed ballast floor, 40 feet diameter with a 3-inch rise towards the centre, the surface being well coated with bitumen before thebottom of thetank was laid. E:tch pair of tanksis isolated with a bund 4 .feet 6 inches high. In designing the tank lay-out, the possibility of the delivery of oil in tank oil barges was not overlooked, the scheme allowing for theerection of a wharf in close proximityto the tanks, the necessary pipeconnection having been putin. From the pump- house a 6-inchdelivery steel pipewas laid up toabout the middle of the long arm of the berth, the end of which was fitted with a valve, and jointed to take a flexible hose which delivered direct into the oil fuel tank of the steamer. Cost.--The cost of theproject under sub-heads of expenditure was as follows :-

i cost of

lraterials, ~ Description of Work. head ~ Labour. l Stores. j&!E Steel sheet piling, timber wharves and landing jetty\ 26,600 , train ferry berth ferry for train ...... i; 13,410

2 ! Dredging berth ...... ~ 3,800 1 1,750 Bridge tower, machinery and signalling equipment . 3,000 I 14,555 Bridgetower foundations ...... 7,900 3,000 Electric powercable ...... 48:; 200 76 Electriclighting for bridge and berth .... ~ 50 Watersupply ...... 550 i 300

8 ~ liailwaytracks, sidings and culvert ..... 5,050 . 1,680 9 Oil fuel depot, pipe and pumps, pump house, etc. . 5,100 ' 1,100 10 Lightapproach channels ...... 1,224 560 11 Mooring dolphins ...... 2,125 1,100 12 Accessroad ...... 600 ' 2,000

iXiscellaneous ...... ~ 1,437 , 350 13 -__ Total ...... 28,500 ' 69,500 ,

Downloaded by [ York University] on [16/09/16]. Copyright © ICE Publishing, all rights reserved. WHARVES. The total length of wharves provided at the port was1,510 lineal yards, three wharves havingbeen constructed, namely; Richborough NewWharf, 790 yards;Richborough Wharf, 330 yards; and to these additional berthage 390 yards in length was added in1918-19. Hicltborougl~ New FVltarf.-In thepreparation of theproject, it was decided that the length of this wharf should be 2,000 feet, and thus sufficient to accommodate fourteen across-channel barges. In decidingupon the site of thewharf, in additionto the provision of sufficient waterarea, questions relating to safety of navigation of approach,railway access, lay-out of sidings, :%rea available in the vicinity for storage, nature of sub-strata, feasibility of future extensions, had to beconsidered : whilst in the design, lay-out, equipment and method of construction of the project, the imperative necessity for its completion in the shortest possible time wits the dominant factor. Thenarrow and tortuous nature of theriver course denied a natural site whichcomplied with the requirements of the project. The formation, therefore, of a new waterway, which would permit of the speedy construction and equipment of the requisite length of wharf, access railway, sidings and approach channel, was obviously the only solution to theproblem. Thesite where the new waterway could best be located 1a.y through the neck of the lowest "link" in the course of the river, just above the straight reach alongwhich the river debouches to its estuary in Pegwell Bay; the wharf, sidings, etc.,were located on the west side of the New Cut, which is bounded on the south.by Stonar Cut, and on the north by MinsterBrook, the distance measured onthe line of this wharf betweenthese limits being about 2,300 feet. Thissite consisted of low-lying meadow-land, wit11 a general elevation of 8.5 feet above O.D., and it was protected against flood by banks rising to a height of 14-75 feet above O.D., being about 1 foot above the levelof the highest recorded tide. The average range of spring tides at the site of the wharf was 10.5 feet, the greatest depthof water in the river here at low-water being 5 feet 6 inches. Thehighest tide recorded during the construction of the wharf occurred on the 14th September, 1916, being 12.5 feetabove O.D. ; thehighest tide known was recorded 011 29th November, 1897, when it rose to 13.95 O.D. Principal Dimensions.-In tbe first instance, so as to allow of the wharf being brought into use immediately on its completion,. the

NewCut forming the barge basin was made 100 feet in width, this being subsequently increased to 300 feet. Thedepth of water in the basin at low-water is 5 feet.The level of the cope of the wharf is 14.75 feet above O.D. Design.-The chief objectsaimed at in thepreparation of the design were such as would ensure that the wharf should be constructed,equipped, and brought into use atthe earliest possible date ; thedesign neqessarily, therefore,had to permit of rapid construction. A corollary to this was that the wharf should be of a lightdesign, which obviouslyprecluded theadoption of heavy equipm.ent, andto realize these premises, theutilization of steel sheet piling for the construction of the wharf recommended itself. The“Universal Joist’’ type of sheetpiling selected, which formed the face of the wharf, consisted of 15-inch by 5-inch rolled steel joists, 40feet long, weighing 39.5 lbs. perfoot run, with intermediateclutches weighing 15.5 lbs. perfoot run. The sheet piling was stiffened longitudinally by two 12-inch by 5-inch rolled steeljoist walings, andtwo 12-inch by 12-inch timber walings bolted to the sheet piling. Steel tie rods 24 inches diameter, connected with the lower steel waling by two 1;-inch bolts, anchor the sheet piling to a concrete wall located beyond the angle of repose of the backing supported by the sheet piling. This wall was oxrried up to thelevel of the surface of the wharf,so has to forma platform wall, and support,ed the runway OF the transporters with which the wharf was equipped. The top of the sheet piling was finished with a concrete wall which forms the cope, and supports the front rail of the transporter runway (Fig. 21, Plate 4). The sheet piling was protected by 12-inch by 12-inch king piles 40 feet long, driven at about 10 feet centres, finished with rubbing pieces, andstrutted longitudinally by two 12-inch by 12-inch timbers.The heads of theking piles were secured to thesheet piling by straps anchored to plates imbedded in the concrete cope wall. Everyfifth pile projected2 feet above thequay level, and wasfitted with a cast-iron cap to form a bollard. Thesurface of the quay along which passes one continuous line of railway track was finished off with a good layer of tar macadam. Bpipnmt.--The origirlal equipment of the wharf consisted of six %ton transporters, spacing 32 feet 94 inches between centres of runways. They overhang the centres of the rail on the dock side by 27 feet G inches, and on the platform side 8 feet G inches. The transporters when loaded move and lift at a speed of 60 feet per minute. Later, six additional transporters were erected, making in all twelve on the wharf.

Nalure of ,Stmfcr.--The strata throughout the length of the Kew Cut, consists of beds of sand and clay overlying a thick formation of very compact impervious green marl, the general top level of which is about 15 feet below O.D., into which the piles are driven to a depth of about 8 feet. Exceptionally hard driving was experienced in the mar),the piles requiring up to 2880 blows to penetrate the last foot driven. Co,/st,,lrc.fio,,.~~-Tnall 1,853 stecl sheet piles with clutches repre- senting 2,374 feet of wvhnrf mere driven in 61 days, work hving lmncommenced on the 2nd June, 1916. In driving these piles four frames equipped with similar hammersto those previously referred to were used. The average number of piles driven per working d:Ly per machine was overthirteen, the greatest number driven in 1 day by one machine was thirty-nine.The excavn.tion of the Cut was commenced on the 29th June, 1916, and with the exception of some littleclearing along the wlmrf face, was completedon the10th November, daring which period 208,205 cubic yards were dredged or excavated. On the 16th September, 1916, the first barge was brought alongside the wharf, sufficient progress having been mnde by thitt date t,o permit of the wharf being brought into use. Table VI11 shows the plantemployed on the excavation of the Cnt and quantity removed byeach ma,chine.

Quantity ’0 I excavated. ---I--.-- ’ CII. Yds.

l’riestman grab So. 1 . . . . . 1 .7.16 ~ 63.16 2,058

’ 9, ,) ,, 2 . . . . . 15.7.16 ~ 19.S.16 1,261

,, ,, 3 . . . . . 30.7.16 ~ 21.5.16 I 1,02S Leubeckerlanddredger . . . . . 31.7.16 26.9.16 25,212

Dredger ‘I Orkney ” ...... 29.6. 16 1 6.10.16 , 7G,735

,, “P.L.A. G” . . , . . 21.7.16 ’ 3.11.16 ~ 94,380

,, “March” ...... 28.5.16 ~ 10.11.16 3,350 By hand ...... 1,145

Total . . . . .’ l .. i 2057205

Theerection of the%ton transporters was commenced on the 6th October, and by the 3rd November five were ready foruse. RniZu>ays.-Siding accommodationaggregating 11 miles of railway track was provided in the immediate vicinity of the wharf, the Iag-out being arranged so as to reduce as far as possible the length of shunts.The area occupied byrailway sidings, offices, and storage ground extended to 52 acres. The water area of the basin, the areaof the yard, and the length of sidings per yard of quay, was therefore 0.0663 acre, 0.066 acre and 24h yards respectively. Surface Drainage.-As the area occupied by the yard and sidings was water-logged and liable to flood, the construction of a system of surfacedrainage had to be undertaken. The main collecting drain consists of a 24-inch reinforced-concrete pipe, the subsidiary drains consisting of 12-inch by 6-inch pipe, tile drains and surface channels. The main drain discharges into the Minster Brook in a reach in which the level of the water can be maintained by sluices at a heightunaffected by the rise of thetide, thus ensuring uninterrupted discharge. Nouenlent of .Wharf.--In a wharf of the design andnature adopted in the construction of the Richborough new wharf, some movement in theline of the wharfface after completionmay reasonablybe anticipated. Observations extending over a considerable period show that two movements have occurred, namely, a permment set forward and a continuous forward and backward movement of marked regularity synchronizing with tides. It is inevitable that in the driving of the piles, introduction of tie rods, and dredging from the wharf front, the face line of the xvharf willsuffer distortion, while further movement will occur until such an elastic structure comes to rest under the stresswhich it normallyhas to resist. For a certainperiod after completion movements may therefore be anticipated. After, however, sufficient time has elapsed for the structure to come to rest under normal conditions of loading, any considerable movement should be viewed with suspicion. In the case of the Richborough new wharf, after the date from which observations for deformations, other than those due to con- structional reasons were made, practically no movement occurred throughout considerablelengths. Actually, over 90 percent. of thelength of thewharf, the greatest movement detected was I& inch,the movement in the remaining 10 percent. not exceeding 2* inches,These limits were,however, not permanent, :CS lat,er meastirements showeda decided movement back towards the

Downloaded by [ York University] on [16/09/16]. Copyright © ICE Publishing, all rights reserved. 190 ROBERTSON ON RICHBOBOUGII hlILITARY [Minutes of original face line. In all, the greatest movement of the face of the wharf from the line to which it was actually set out, didnot exceed 59 inches. Widening qf Barge Basin and Increase in E~.rL~,llenf.--7itll the progress of the war, the increased demands on Richborough as a transportation depot made it evident that development of resources to theutmost of itslimits was imperative. It was, therefore, decided to increase the width of the barge basin to 300 feet for the accommodation of more craft, and to augment the equipment by six 5-ton and one 10-ton electric gantry cranes, t8he jibs of which could plumb two bottoms and two lines of railway track. The total equipment of the fifteen berths comprised within the wharf is shown in Table IX :-

TABLEIS.

5-Ton ~ 2-Ton 11 1 5-Tan 1 %Ton No' Gantry Crane. ~ Transporter. Berth iYo' GantryCrane. Trallsporter.

In the case of the 10-ton crane, the greatest load transmitted to the runway on the quayside was 44 tons, on R wheel base 3 feet 14- inch long. When this 1o:td came on either of the front wheel bases, the load on the remaining front wheel base was 23 tons, and on the corresponding back axles 24.55 and 16.5 tons respectively. In thecase of the 5-ton cranes, theloads in corresponding order were 28$ tons, 18 tons, 18 tons, and 12 tons, The decision further to equip the wharf with these cranes led to very considerablediscussion as to thefeasibility of supportingthem on the runway for the %ton transporters, or the advisability of providing a new runway supported by an entirely new structure. It is not necessary here to recapitulatethe arguments, often supported by claboratecalcula- tions, which were advanced for and against the proposals ; the deci- sioneventually taken was toprovide for thecranes an entirely

Downloaded by [ York University] on [16/09/16]. Copyright © ICE Publishing, all rights reserved. Proceedings.] TRANSPORTATION DEPOT. 191 new runway supported by a structure independent of the existing wharf, As theelectric gantry cranes for working purposes could be Iocated permanently at certain berths it was not necessa;y to con- structthe runway for the entire length of thewharf. In all 892lineal feet of runway was constructed, 435 feet at berths Nos. 1, 2 and 3, 106 feet at berths Nos. 9 and 11, and 245 feet at berths Nos. 13 and 14. Therunway supporting the rail on whichthe cranes travel consists in the case of the10-ton crane of three,and in the case of the&ton crane of two,15-inch by 5-inchH-beams carried on pilesspaced 10 feetapart. To minimise the possibility of damage being sustained by the wharf, fromthe compression resultingfrom driving the piles forthis new runway, steel cruciform piles built up of two H-beams were drivenfor the support of thefront runway, the back runway beingcarried on 12-inch by 12-inch timber piles. The piles were tied transversely by two clutch bars bolted to the pileheads. Cost.-The total expenditure incurred in the construction of the original project was $153,616. This amount does not include the cost of the 10- and 5-ton crane runways,or certain extensionssubse- quently made to the siding accommodation. The cost of materials and stores used in the original works amounted to $109,000, the diEerence being the cost of labour and supervision. Tro&c.--The totaltonnage of exportand import traffic dealt with at thewharf from date of opening to 31st December, 1918, is shown in Table X (p. 192). Richborough Wha.rf.--This wharf is situated 2,200 yardsup- streamfrom the new wharf, and extends along the left bank of R comparatively long straight reach of the river for a distance of 330 yards. A part of this wharf, 86 yalsds in length, was originally constructedby Messrs. Pearsons in connectionwith the Dover Harbour Works. The extension consisted of steel sheet piling, mostly similar to that used in the new wharf, protected by timber fenderpiles, and was anchored to concrete blocks by 2i-inch diameter tie rods;the wall being finished with a light timber cope carried on the fender piles. Two lines of railway track with cross-overs at berth extended along the entire lengthof the quay front. The equipment consisted of three B-ton, and one 15-ton Scotch derrickcranes. The cranes are placed behindthe railway track, thejibs being able toplumb barges moored alongside the wharf. Store warehouses covering in all an area of 5,800 square yards

Downloaded by [ York University] on [16/09/16]. Copyright © ICE Publishing, all rights reserved. 192 RODERTSOS ON RICHBOROUGH MILITARY [Minutes of TABLEX. - l1 Month. ! Export. Import. Month. Export. Import. ' _-l __- 1 'TOUS. ' Tons. Tons. Tons. 1916 1 1' 1918 ~

Up to 31 Dec. 1,969 .. l1 January . . 42,242 5,439 l l 1917 I-- i February . ~ 46,721 B,096 Jauuary . . I 5,577 I March , . ' 55,909 ti,911 12,054

6, S50 l April . . . ~ 1,091 .. ,l 1 June . . . ' 73,260 8, SO2 MiLY . . . , 33,901 9.35 , 4,595

July . . . 47,017 9,507 ~ August . ' 5,982 . 1 August . . 51,010 57992 '1 September . ~ 73,860 9,225 September . 53,290 3,254 i October . . 92,942 4,183 October . . 37,237 4,141 29,658 2,605 November . 45,075 , November , 'l i December . . 32,SS6 11,422 December . 3,141 __-__ ~ 21,026 Total for 1917

extend along the downstream half of the wharf, from which in :m upstream direction extend the engineering workshops. The upstream end of the wharf led to the repair slipway, beyond whichlay the shipyard. About half of thelength of the wharf was therefore used for the export and import of stores, the remaining length being utilized as fitting-out berths for barges and tugs under construction and repairs. The total tonnage, export and import, handled at this wharf up to t'he 31st December, 1918, was 195,333 tons. Brlditiomxl Bert7mge7 1918.--ln the spring of 1918 the increasing demands for transport facilities a6 the port made it evident that additional wharfage was necessary. Here again rapid construction was imperative, but the question was now further complicated by the national necessity for economy in the use of steel and timber, :md the difficulty of obtaining immediately suitable cranes for the equipment of tLcwharf. Above all it WUB recognized that the

wharf was essentially a “ war work,” the need of which, not being permanent,required the provision of astructure of a temporary nature, the materials and equipment of which would be recoverable on the necessity for them ceasing to exist. The new berths were required to accommodate four 1,000-ton barges, each 187 feet long. Proposals were examined for the provision of the requisite length of wharfage on the east side of the barge basin, and on the left bankof the pool below the train ferry berth. The site, however, eventually selected for theadditional berths, lay between the train ferry berth and the north end of the new wharf. The more immediate advantage accruing from the adoption of this site lay in the economical access obtained, and the fact that, for purposes of control and movement, the proposed wharf formed an extension of the existing wharf. The crane equipment readily obtainable consisted of 5- and 3-ton Scotch derricks. The king post and base of each crane was carried by a group of 12-inchpiles around which, alsocarried on piles, extended a working platform. The back struts of the cranes were securedto an independentdouble pile anchorage.The platforms round the cranes were carried out so as to form dolphins against whichthe barges were moored. Thebollards consisted of 12-inch by 12-inch piles driven along the bank. The cranes were arranged to plumb two linea of railway track and both holds of the barges; two cranes commanding ten ordinary wagons were provided at each berth. The sidings, excluding the two.tracks along the quay front,could accommodate 100 full and 100 empty wagons, the capacity of the cranes at one berth being about 25 tons of general cargo per hour. The site of this wharf, in addition to being low-lying and’ constantly liable to flood, was intersected by the channel of Minster brook. It was necessary, therefore,to raise the surface of the entire area occupied by the lay-out to a height of 6 feet, and to provide for the discharge from the Minster brook through a 3-foot by %foot culvert 280 feet long, fitted with a tidal flap and sluice gate.

GRIDS. For the repair and overhaul of the craft frequenting the Port, grids were provided in the Pool and above the new wharf. The grid in the Pool is 165 feet long and 30 feet wide, the working platform beingabout 1 foot 6 inches,and the top 4 feet 6 inchesabove L.W.O.S.T., giving working periods on these tides of about 3 and 5 hours respectively (Figs. 22, Plate 4). [THE INST. C.E. VOL. ccx.] 0

The distribution of the supporting piles was arranged to take the heaviest dredging craft employed on the work, and the arrangement of the carrying beams was designed to facilitate the repair to the doors of the largest steam hoppers. Thegrids above the new wharf can take three across-channel barges. The platform and carrying beams of these grids are 3 feet higher than those of the lowergrid. For the accommodation of tugsunder repair a smalljetty, with a workshopequipped with the necessary tools, was provided at this site. Repairs could, therefore, be effected to tugs and barges in the immediate vicinityof the wharf,thus obviating the necessity for towing the craft to the higher reaches of the river.

SLIPWAY. The slipway for thereception of bargesrequiring repair and overhaulwas located in the shipyard, and in close proximityto the engineeringshops. The depth of waterover the cradle at H.W.O.S.T. is 3.75 feet. It was originallyconstructed to take one across-channel barge, but it was later enlarged to take two of these barges, or one 1,000-ton barge, It was formed with a width of 43 feet 4 inches, with an inclination of 1 in 26, and equipped with a 10-ton steam hauling winch run from the compressor house boilers. RAILWAYS. The total length of railway track operated at the Port extended to 56 miles. The track consistsof 75-lb. British Standard Section flat-bottomcd rails, 36 feet long,laid on thirteen sleepersper rail-length and securedby dog spikes. Wherethe size of the sleepersfell below the standard, 9 feet by 10 inches by 5 inches, the number laid per rail-length was increased. In thecase of the tracksover which trafiic was considerable, steel bearing plates, 8 inches by 8 inches, w-eighing 123 Ibs. each, were introduced between the rail and thesleeper. The standard crossing through the Port railways is 1 in 7 with 12-foot switch rails, nearly all of which were made in the military workshops at Richborough. The tracks were raised to ensure satisfactory drainage. The filling for the embankments was excavated from Weatherlees Ell, a small eminence,over which thealignment of themain access railway passed, and which encroached upon the site of the reception sidings. Excavation was effectedby means of a Ruston-Proctorsteam

navvyand a Luebeakerland dredger. The ballast for thetracks was obtained from the local deposits, and consisted chiefly of the dirty ballast overlying the clean sand and ballast. Previous to the inception of the Richborough scheme, a railway siding, branching from a point about 12 mile north of Sandwich Station,on the Deal branch of the South Eastern and Chatham Railway,gave access tothe gravelpits and wharf which were workedby Messrs. S. Pearson & Sons, Ltd., during the construction of theDover Harbour Works. This siding wasused during the early days of construction for the delivery of materials, and it was fromthis siding that the original servicelines for the construction of thewharves and camps extended. This siding eventually, on the completion of the new access railway, .remained and formed theconnection of theRichborough Salvage Transit Depot with the South Eastern and Chatham Railway. The new access railway to the port and depot forms a junction with the Deal branch of the South Eastern and Chatham Railway at a point about 1 mile south of Minster Junction Station. From here the railway runs ina south-easterly direction across the Rams- gate-Sandwich Road to the new wharf and traiii ferry berth. The main track then continues along the east side of the road through the Saltpans Yard and crosses the Stonar Cut on a 40-foot girder bridge, immediately after which it branches into two tracks, one continuing along the east sideof the road, the othercrossing to the west side, so as to give access to the blockyards and storage yards. These tracks eventually unite and terminate in the lay-out of sidingsformed around the workshops, shipyards, store sheds, wharf!, etc., all of which are generally comprised in what is known as the Richborough Yard, from which sidings extend to the camps and ballast pit. Weatherlees Yard.-The main group of sidings for the reception, marshalling,and despatch of trafficto and from the Port lies between the junction with the South-Eastern and Chatham Rail- way and the crossing of the Ramsgate-Sandwich Road, and is known as the Weatherlees Yard. The average numberof wagons handled dailyin this yardwas 1,473. From the Weatherlees yard the main line crosses the Ramsgate- SandwichRoad on the level,immediately after which access is gained to E--

(U) The train ferry sidings. (b) The additional berths. (c) Saltpans Yard for the new wharf, 02

Truin Ferry Sid,ings.-The sidings in the immediate vicinityof the trainferry berth for the reception of made-uptrains awaiting despatch,and for the accommodation of stockfrom the ferry steamers, consisted of twogrids, each comprisingthree lines of track, eacll trackbeing of sufficient lengthto hold aboutthirty wagons. These grids converged into two main tracks corresponding to the two centre tracks on the railwaydeck of the steamers. Additional or Jetty Berth Sidings.-The sidings, excluding the two tracks along the quay front,provided standing room for 100 full and 100 empty wagons with the necessary engine lines to facilitate the movement of this number of wagons. Snltpans Yard.,The length of track in these sidings extended to about 11 miles and consisted chiefly of the wharf sidings, ammuni- tionsidings, and stacking yard sidings, extending to G miles, 3 miles, and 2 miles respectively. Theyard was laid out so thatall traffic forexport from the wharf was taken to the yard direct, where, on arrival,was it sorted in the extensive sidings provided for this purpose. Prom these sidings it was worked to the herths, the emptywagons being worked througll to the empty wagon sidings from which theywere either drawn for “ backloading ” or passed out over the departure line. Ammunition was forthe most part received in completetrain loadsand passed directto the ammunition sidings, which had :I capacity for 300 wagons. Here,prior to the transmission to the wharf, the traffic was sorted according toits port of destination. Richborough Yard.-This yard comprised thesidings in and aroundwhat may be termedthe industrial centre of thedepot, as this is the area in which the warehouses, workshops, shipyards, power houses, ballast and sand pits, etc., were located, and in the vicinity of which lay the blockyards. These sidings over which, owing to the very varied activities at thiscentre, very considerable traffic movement was called for, provided accommodation for about 325 wagons. Richborough Salvage Transit Depot.-This salvage depotlying beyond the great loop in the course of the river in which the depot lies, was not connected with the depot railway system, access to it being obtained fromthe South Easternandchatham Railway, overthe sidings previously constructed byMessrs. S. Pearson and Sons, Ltd. The lay-out of this yard, in addition to providing sidings capable of holding 500 wagons,comprised a largemarshalling yard for sorting inward and outward trafic, fromwhich access was gained to a series of sidings,laid out to form a yardfor the reception of engineering plant evacuated from France.

Downloaded by [ York University] on [16/09/16]. Copyright © ICE Publishing, all rights reserved. Proceedings.] TRANSPORTATION DEPOT. 197 Si~pallingArrangements.-As for the most part the railway consisted of a series of shunting yards linked up for through working, no system of fixed signalling was provided. The through main line running from the junction with the South Eastern and Chatham Railway to Richborough Yard serves in turn nine large yards,innumerable sidings, andcrosses the Ramsgate-Sandwich road three times. The whole system was divided into five sections, at the entrance to each of whicha control station connected to the traffic telephone circuit was placed. When a train was ready to leave a section, the signalman com- municated with the cabin ahead and asked for permission for it to proceed. Having obtained this, he directed the driver accordingly. No train was allowed to pass a cabin without permission. The only electrically-controlled signals on the system werefor the operation of the traffic to and from the trtin ferry steamers, where two sema,phore signals and an overhead disk signal, interlocked with the catch points situated between the grids and the berth, were provided. Rolling Stock.-To deal with the local movement of the material and plant required during the construction of the depot, and in the operationsundertaken at storeyards, wharves, workshops, shipyards,etc., the railway system was equipped with 519 wagons, seventeen passenger coaches, and thirty-one locomotives, Table XI. The duty of the wagons was about 100,000 tons per month, the engine mileage being approximately 2,800 per day. TABLE XI.-EQUIPNENTOF ROLLINQSTOCK EYPLOYED.

Wagons. Passenger Coaches. Locomotives.

~ ~ Description. Description. Maker. . ~~~ ____-~---- 1 inspection 3 19-inch 4-4-0 G. E. Rly. Co. saloon 2 l7 ,, 2-4-2 L. & N. TV. Rlg. Co. 14 4 - wheeled 4 17& ,, 0-6-0 Xanningand Wardle doublebolster 1 4 - wheeled 1 16B 0-6-0 G. E. Rly. Co. wagons first ,, I 16 ,, 0-6-0 Andrew Barclay 39 19 ft. 6 in. 6 16 ,, 0-6-0 HudswellandClarke flat wagons wheeled 2 4 - 1 16 0-6-0 PearsonandKnowles seconds ,, SS open high-side 2 15 ,, 0-6-0 Manningand Wardle wagons 1 14 9, 0-6-0 9, $9 ,, 1 4 wheeled - 2 12 ,, 0-6-0 S. E. & C. Rly. Co. 197 opcplow-side ' brake, third wagons 2 12 ,, 0-6-0 Manningand Wardle 1 12 ,, 2-2-0 L. L% S. W. Rly. Co. 172 side tip l2 G. F,. Rly. 6- ! rvngons i n~heelalthirds

c_^-- -__1__

SANDAND GRAVELSUPPLY. Theexistence of extensivedeposits of shinglethroughout the area occupied by the depot was not without influence when the site of the new port and depot was underconsideration. To the fact that the valueof these deposits was rightly appreciated andrealized during the early discussions can be attributed much of the speed and economy with which theexpansion of the depot was carried out. Thedeposits wereopened up at severalplwes, but by far the greatest quantity was excavated in the vicinity of Stonar camp by extending the north and south lakes. In all 250,000 cubic yards of gravel and sand were excavated, the maximum output reaching951 cubic yards on 17th February, 1917. Above water-levelthe shingle was excavatedby steam navvies and by hand, andbelow water-level it was raised by 5-ton locomotive cranes,fitted with single-chain half-tine grabs of 4 cubic yard capacity ; crushing and screening plant was provided in the pit for thesupply of materialsfor the manufacture of blocks and other concrete work.

MECHANICAL SECTION. It llas been stated at the commencement of this Paper that the establishment of the Richborough Military Depot arose from the necessityfor the construction of barges and the provision of the wharfage from which to operate a barge service for the tmnsporta- tion of military stores. The acknowledgment of the necessity which warranted the provision of these services premised the undertaking of a large number of auxiliary works; thus, large camps with their sewerage, water, road and other services, were required for the accommodationof the constructionand operative staffs. Railways, approach channels offices, etc., were indispensable for the workingof the wharves, while only by the construction and proper equipment of slipways, power houses, workshops, foundries, etc., could the provision of the necessary barges be ensured, and other engineering workof a mechanical nature, including the supply of power, water, etc., be undertaken. The lay-out of workshops and shipyards covered an area of 47 acres, of which 43 acres were roofed-in. The surface of the entire, area occupied by the workshops and shipyards had to be raised 4 to 8 feet before it could be cpnsidered sa,fe frop inundation at periods of high-water,

The earlier buildings were constructedof concrete blocks, moulded onthe Winget principle, but later extensions consist of steel framing with corrugated iron sheet walls.

POWER. The whole of the electricity for both power and lighting of the variouscamps, workshops, wharves, train ferry berths, etc., was generated at ,a central power-station, which was equipped with up- to-date steam-driven plant of the capacity of 750 kilowatts. In the boiler-house there were three Babcock-Wilcoxboilers, each with an evaporating capacity of 6,000 Ibs. of water per hour, fittedwith super-heater and chain-grate stoker of theusual Babcock-Wilcox type. Thefuel used exclusively was East Kent (Tilmanstone)slack, which was found to give very satisfactory results. The engine-room plant consisted pf two 250 kilowatts 220 volts direct-currentgenerating sets, and one 250 kilowatts 3,300 volts alternating current 50 periods alternator, each exhausting into an independent surface condenser, with steam-driven auxiliaries, In addition, asa stand-by to the steam alternator, therewere two 100-kilowattmotor alternator sets to convert the direct-current supply into high-tension alternating current. The high-tension switchboard was of the totally enclosed sheet metalworkshop type, and consisted of threegenerator and two feeder panels. The 220 volts continuous-current supply was used as a two-wire distribution for supplyingthe workshops and camps adjacent to the power-station. The high-tension supply was distributed to the outlying districts by two overhead feeders to five substations.Three of thesewere fitted with static transformers stepping down to 220 volts three- phase 50 periods. The remaining two substations were equipped with rotary con- verters, converting to 220 volts direct-current two-wire for power supply, to the electric cranes and transporters, etc., on and around the main wharf. Some idea of the extent towhich electric power was used over this area maybe gained fromthe followingfigures. Duringthe year 1918 the maximum load on t'he power-house was 600 kilowatts, and over I&million units were generated during the 12 months under consideration. In all,there were approximately 370 motors of digererept siFes uy to 50 $lP. ip use in tbe various partsof the works.

Thelamps in use forlighting were equivalentto approximately 8,400 20 watt lamps.

COXPRESSEDAIR SUPPLY. The supply of compressed air for working the pneumatic plant and tools in the shipyards and workshops was obtained from three Alleyand RIcLellan vertical high-speed air compressors,each capable of delivery of 3,000 cubic feet of freeair per minute. Theboiler house equipment consisting of fourThompson boilers fitted with underfeed mechanical stokers.

SEIPYARDS. The shipyard in which was located the repair slipway, consisted of twenty-five building slips lying on both sides of the river, and connected by a 40-foot span swing bridge carrying a single line of railway track and footway. The slips on the left bank of the river were completed with access railway, sidings, etc., in the autumn of 1916. Theextension of theright bank was undertaken later to meet an urgentdemand for the construction of seaplanetowing lighters. The barge building slips, which were on the left bankof the river, were 190 feetlong, the slipway being 72 feetlong laid to an inclination of 1 in 12, the width between the centre of slides being 10 feet.The building berth was 120 feet long, of whichlength 105 feet was formed to an inclination of 1 in 04. The slips on the right bank of the river for the construction of seaplane lighters were laid to an inclinationof I in 12, and consisted of 4 feet Sh inches railway track. The plating shop on the left bankof the riverwas 250 feet long by 50 feet wide, and was equipped throughout withan overhead system of runways, capable of lifting 2 tons, the shop on the right bank being 192 feet long by 30 feet wide. Since the erection of barges and other craft was commenced at theend of 191G, the followingvessels have beencompleted and launched :-l25 A.C. barges, four compositebarges, one tug, thirty- four58-feet seaplane towing lighters, twelve A barges, four pontoons, and fourteen motor barges ; in addition to which reImirs to the following craft have been carried out in the case of 5,506 barges, 113 motorlaunches, seventy-five specialbarges, 208 tugs, and 312 miscellaneous craft. An interesting incident in the work of the yard was the building of R cross-channel barge by means of electric welding, no riTets

being used in the construct,ion. The vessel, which was the first to be built completely by means of electric welding,proved entirely satisfactory in cross-channel service.

WORKSIIOPS. The machine, smiths’, fitting and erecting shops consisted of a building of three bays, each 240 by 45 feet, the first being divided intolight machine shops, heavy machineshop, and toolroom. The majority of the light tools were belt-driven, while the heavy machines were mostly driven direct from motors. The light machine shopwas served by a system of overhead runways which extended to the stores and stock yards, and the heavy machine-shop was served by two 5-ton overhead travelling cranes. Thetool room dealt with the manufacture of toolsfor the machine shop, smithy, and the works generally and the grinding of tools and drills. The smiths’ shopwas divided into smithy, pipe andcoppersmith’s shop, and bolt and screwingshop. In thenew portion of the smiths’ shop, t,he smoke was exhausted by a system of overhead trunking with draught induced by a motor-driven fan. The fitting shop, at one end of which was a small brass shop, equippedwith machine tools, hada service of overheadrunways that served the benches and had connection with the outside system of runwaysto the stores and stock yards. An inspectionand finished store was provided for the parts manufactured in the other shopsand awaiting assembly. InL theerecting shop, whichwas 26 feet high to the underside oft:he roof-trusses, were two 10-ton overhead electric travelling cranes, and a pit for the locomotive and crane repairs. Satcmill and Carpenters’ Shop.--The sawmill and carpenters’ shop consisted of :- Feet Carpenters’ shop, EL bay ...... 133 by 25 Sawmill, 2 bays, each ...... 132 ,, 25 Log band saw house, and saw and tool grindery, 2 bays each ...... 50 ,, 40 In addition the mould loft in connection with the shipyard was located over one of the bays of the sawmill. Permanent- Way Shop.-This shop consisted of a building 190 feet by 45 feet, and in addition to the manufacture of standard points and crossings, which at one period1 were turned out at the rate of forty sets perweek, specid work such as scissors, diamond-crossings and. other permanent way material wm deslt with,

Tractor Repair Shop.-This shop, which was erected in response toan urgent demand for facilities to repair petrol electric and petrol tractors forthe light railwaysin France, consistedof a building 300 feet by 36 feet, equipped with two overhead electric travelling cranes. The shop, which had an extensive store for the component parts of tractors, had also a small machine shop for the repair work of engines and other parts of tractors. Steel Construction Shop.-This shop, 300 feetby 36 feet, which adjoined the tractor repair shop, dealt with the under frames and bodywork of thetractors and other structural work, and was equipped with punch and shears, drills, and hydraulic riveters. Foundries.-These consisted of :- (l) Pattern shop, 50 feet by 25 feet, with a good equipment of wood working machines. ('2) The brass foundry equipped with a half- ton cupola,200-lb., tilting furnace, and a three-pot underground furnace, the major portionof the materialused for brass castings was obtained from cartridge case scrap. (3) The iron foundry was a building 140 feet by 45 feet with two 5-ton overhead travelling cranes, and was equipped with one5-6-ton cupola and one 3-toncupola, whichwere provided with a staging and electric hoist.

TELEPHONEAND TELEGRAPHSERVICES. The works were equipped with an up-to-date post office exchange, havingupwards of 140 extensionsand possessingspecial trunk facilities for communication with theWar Office and the Admiralty, and with the surrounding districts. The works were equipped with their own telegraph office for ,the purpose of dealing with the very large number of messages passing in connection with the movements of craft and transportof stores.

WATER Supmy. Thesupply of materfor camp services was obtained from the Sandwichand Ramsgate Corporations' mains. From the former service the supply was delivered through a G-inch diameter pipe to three 40,000-gallonreinforced-concrete tanks and three cast-iron tanks,having a capacity of 20,000, 10,000 and 7,250 gallons respectively, located throughout the camps. The extension from the Ramsgate main consistedof a 3-inch pipe, from whichdistribution throughout the camps in thePortBern sectiop of the depot was qnde direct,

For the supply of waterfor the works, locomotives and fire services,water was pumpedfrom the upper reaches of the riverthrough a 5-inch diameter pipe to a 60,000-gallonwater- tank 50 feet high, situated near the workshops, from which distribution was made throughout the works and camps. The pumping installation consisted of two electrically-driven pumps, each capable of delivering 9,000 gallons per hour a,gainst a head of 120 feet. The total length of water pipes laid extended to about 38 miles. The average consumption of water in the camps was 10 gallons perhead per day, the average works consumption being 160,000 gallons per day.

The Paper is accompanied by drawings and prints, from which Plates 3 and 4 and the Figures in the text have been prepared.

Downloaded by [ York University] on [16/09/16]. Copyright © ICE Publishing, all rights reserved. APPENDIX.-I. W. & D., R.E., Lrwr CRAFT - OF -! Jliuinlun1. laximum Bucket Name of Vessel. Length. Beam. Draught. Dredging Dredging apacity. Depth. /cDepth. __-____l - -- -_-- -- Ft. Ins Pt. Ins. Ft. Ins. Ft. Ins. :ob. Ft. DredgcTS. D.8. ‘‘ Cachalot” . 185 0 35 0 10 0 3s 0 12 0 16

~ “P.L.A.6.” . ’ 214 0 40 0 90 55 0 10 0 27

D.10. “P.L.A.5.” . ’ 138 0 30 0 80 45 0 90 10 D.7. “India” . . 1.42 0 35 0 S6 45 0 96 15 ,1 D.I. “Venezia” . i 148 o 28 0 70 45 0 19 0 20 J1.2. ‘LIpswich” . 133 6 25 0 66 35 0 10 0 10

D.3. “Orkney ” . 125 0 21 6 40 35 0 10 0 14 “ Fannerden ” i I I).6. “Xarch” . . ’ 52 0 20 4 3 0 ;l7 6 50 3

“ Samphire ” . 95 0 25 6 .. ..

D. 12. ‘ Riparian ” . 31 0 63 “ l ’. D.5. ‘‘ Cruachan ’’ . 29 0 so

10 0 1 .. Light i ft. 6 ins Water in .’ ’ .. i jtern 9 f t. i 46 70 67 .. 67 Moulded depth .. l i ft. 6 ins 76 Depth 50 ‘’ i

RICHBOROUGH, DREDGING. EMPLOYED.

......

www ......

d 00 0 0 0 000 0 0 0000 ___ ...... y...... z h S...... 0

WATERLOW & SONS LIMITED,LATE THOP.KFLI. a SON,LOXDON. Minutes of Praccsday. of The lnrtitutian of Civil Engineers, Vol. CCX. Session 1919.2&-t 11. J. K. ROBERTSON. Downloaded by [ York University] on [16/09/16]. Copyright © ICE Publishing, all rights reserved. Minytes of Prowedinw of The Institdtion'of Civil Engineers, Vol. CCX. Seasion 1919.20, Part II. Downloaded by [ York University] on [16/09/16]. Copyright © ICE Publishing, all rights reserved. i