272 WARING ON TIIE CEYLON GOVERNMENT RAILWAYS. [Selected SECT.11.-OTHER SELECTED PAPERS. (Paper No. 3010.) ‘I The Haputale and Bandarawela Extensions of the Ceylon Government Railway, with Notes upon other Railways Recently Constructed in the Colony.” By FRANCISJOHN WARING, M. Inst. C.E. THEobject of the present Paper is to supplement those presented to the Institution by Mr. J. R. Mosse, M. Inst. C.E., in 1880,’ and by the Author in 1887,2 by an account of the recent exten- sions to the Ceylon Government Railways, all of which are of 5 feet 6 inches gauge, with particular reference to the Haputale and Bandarawela Railways, where the magnitude of the works, entailed by the difficult country traversed, offers special points of interest. THE HAPUTALERAILWAY. This line isa further extension, about 254 miles in length, into the Province of Uva, of the Nanuoya Railway, and crosses the main dividing ridge of the island, traversing a country evenmore broken and mountainous than that through which the Nanuoya line passes. Its construction was sanctioned by the Secretary of State for the Colonies in February, 1888, and the workswere begun on the15th March, 1889; theintervening time having been occupied in engaging and sending out the staff, despatching to the Colony the necessary plant and materials, acquiring the land and other preliminaryoperations. Curves and Gradients.-Starting at Nanuoya, 5,292 feet above the sea, it rises, at the summit at Pattipola, Ilk miles distant, to analtitude of 6,224.5feet, and thence falls to 4,698 feet at Haputale. The following is a summary of the gradients :- l Minutes of Proceedings Inst. C.E., vol. lxiii. p. 63. Ibid, vol. xc. p. 319. Downloaded by [ University College London] on [21/09/16]. Copyright © ICE Publishing, all rights reserved. Papers.] WARING ON THE CEYLON GOVERNMENT RAILWAY. 273 From 1 To Rise. Fall. 1 ($,,:$. ------1 Dlstauce. __l -_. 1 Chains. Feet. Feet. .. 1 in55.09 370.00 261.65 .. 1 ,, 93.33 --1,526.50 1 ,, 47.81 Totals . 1 2,035.80 932 50 1,526.50 I--\-- I--\-- Deduct rise in feet . 932.50 Total fall in feet between termini . 591.00 1 Thelimiting gradient of 1 in 44 is used in five cases for an aggregate distance of 9 miles 21 78 chains, the longest continuous length being 3 miles 5 chains. The sharpestcurve, 5.06 chains in radius, occurs twice, the aggregate length being 11 -43 chains. Thesharpest curve on the 1 in 44 gradientis 5.22 chains in radius. The aggregate length of curves under 7 chains in radius is 10 miles 4; 99 chains. Of the total length of the line 64. l per cent. is on curves of thirty-one different radii. Meteorology.-From records taken at various points during con- struction of the line, the average rainfall of the district traversed appears to be about 100 inches per annum, falling on upwards of 200 days, the rainfall and number of wet days both being some- what greater at Nanuoya than at Haputale. The maximum fall recorded in any one day was 8 61 inches at Nanuoya on the 4thJuly, 1892. Duringthe south-west monsoon thediurnal velocity of theair at Pattipola,as registered by a Robinson anemometer, was frequently for weeks together between 500 miles and 800 miles, and on the 8th July, 1892, it reached 1,103 miles, the velocity between 11.25 A.M. and 12.25 P.M. on that day being 73 miles per hour, equal, by the formula P = V2 X 0.005, where P is pressure in lbs. per square foot, and V is velocity in miles per hour, to a pressure of 26.645 lbs. per square foot. It will be readily understood that the prevalence of rain for so many days yearly,often accompanied by violentwinds, coupled with the peat altitude above the sea of the whole line,rendered the climate very inclement and distasteful to the labourers, mostly Tamils from Southern India or Sinhalese from the lower and more genial districts of the island ; and at theoutset, until they became acclimatized, it was only with the greatest difficulty that they could be induced to remain on the work. Earthworks.-The cuttingsand embankmentswere formed to [THE INST. C.E. VOL. CXXXI.] T Downloaded by [ University College London] on [21/09/16]. Copyright © ICE Publishing, all rights reserved. 274 WARING ON THE CEYLON GOVERNMENT RAILWAY. [Selected the sections described in the Author's previous Paper. The total quantity of excavationwas 2,292,964 cubicyards, equal to an average of 89,920 cubic yards per mile, of which 542,948 cubic yards, or nearly 24 per cent., was gneiss or quartz rock. Tunnels.-There are nineteen tunnels, aggregating2,319-4 lineal yards and varying in length between 350.5 yards and 22 7 yards. From surface indicationsit was thought that most of, or, at least, the longer tunnels would be through solid rock, and two complete sets of compressed air-tunnel drilling machinery were sent out. Each set comprised a direct air-compressor, with engine cylinder 12 inches in diameter by 16 inchesstroke, a steel air-receiver 10 feet long by3 feet in diameter, and three No. I11 Schram rock- drilling machines 34 inches in diameter, with air-pipes and spare parts,and a 15-HP. boiler. The Fig. 1. heading of tunnel No. 3, 298.1 E yards in length, was driven almost entirelyby this machinery. As a rule, however, the tunnels proved to be either through soft material imbeddinggneiss boulders or through loose and fissured gneiss orquartz rock, andthey were thereforeexcavated by manual labour. HALF SECTION HALF SECTION Thenature of the materialren- UNLINED 1 LINED dered it necessary to line most of Scale, 1 inch = 16 feet. the tunnels for the greater part of their length. At first masonry in cement was used, but owing to the scarcity of good masons, the frequent absence of suitable stone near the tunnels and the time which would be thus entailed in completing the work, it was generally abandoned except for the entrance lengths and in very heavy ground, and as good bricks were not procurable the use of cement concrete in mass was ulti- mately adopted. The section usually employed for unlined or for wholly lined tunnels is shownin Fig. l ;and thatfor tunnels where arch lining only wasnecessary is shown in Fig. 2. The thickness of the lining was usually 18 inches, though this was increased in tunnel No. 13 to 2 feet and in part of tunnel No. 12 to 2 feet 6 inches, in part of which also an invertwas built. The smallness of the clearance between the line of minimum structure and the tunnel rendered it necessaryupon curves to incline the axis of tunnel from the vertical so that it should be at right-angles to the plane of the rails, andthis entailed considerabletrouble Downloaded by [ University College London] on [21/09/16]. Copyright © ICE Publishing, all rights reserved. Papers.] WARING ON THE UEYLON GOVERNMENT RAILWAY. 275 when the tunnels were, as was often the case, on reverse curves. The special sectionadopted for the short tunnel, No. 9, where, to avoid the risk of a slip, it was thought advisable to interfere as little as possible with the steeply-inclined strata of superin- cumbent rock, is shown in Fig. 3. In thistunnel the concrete lininghad a minimumthickness of 2feet and invariably extended to the rock, no packing atthe backbeing allowed. Weep-holes, either of stone or iron-pipes2 inches in diameter, were left at frequent intervals in the lined tunnels, and refuges for platelayers were madein all tunnelsat distances of two chains apart. The concrete was usually composed of one part of cement, two Fig. 2. Fig. 3. SECTION ARCH ONLY LINED TUNNEL N? 9 Scale, 1 inch = 16 feet. parts of clean, sharp sand, and six parts of clean stone broken so as to pass through a 2-inch ring; but for 3 feet at the key 5 parts instead of 6 parts of stone were used. The transport of materials to the tunnels, especially to those on the 18th mile, where eight of themare situated, entailed difficulty and expense. Cementwas brought from a store on the nearest cart road, distant some 12& miles, the intervening country being mountainous, in jute sacks on pack bullocks, the load for each bullock being 50 lbs. to 60 lbs. The sackswere protected by smalltarpaulins, and but little of the cement suffered damage in transit. Sand was obtained from the hillside some 900 feet above the railway, and was sent down in sacks, each containing & cubic yard, by suitable runners travelling on a wire rope 1,000 yards in length, having a fall of about 800 feet to the ground above tunnel No. 12 ; thence it was T2 Downloaded by [ University College London] on [21/09/16]. Copyright © ICE Publishing, all rights reserved. 276 WARING ON THE CEYLON GOVERNMENT RAILWAY. [Selected conveyed by smaller distributingwire-ropes or shoots to the tunnel mouths. Though much of the line passed through forest, most of the trees were stunted and crooked, and much difficulty was ex- perienced in obtaining straight logs of sufficient length and girth for bars and sills, and when they were found, owing to the steep- ness of the ground andthe Fig. 4. absence of roads, in trans- I portingthem 3 miles or 4 miles to the work. The tunnelswere worked from top headings, an& ACE where the ground was heavy,these were, for safety, completed through- Scale, 1 inch = 16 feet. out before widening was METHODOF TIMBERINQIN HEADINGS. begun-The headings were generallybetween 7 feet and 8 feetsquare.
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