Soil Engineering Problems on the Quebec North Shore and Labrador Railway Woods, K
Total Page:16
File Type:pdf, Size:1020Kb
NRC Publications Archive Archives des publications du CNRC Soil engineering problems on the Quebec north shore and Labrador railway Woods, K. B.; Pryer, R. W. J.; Eden, W. J. This publication could be one of several versions: author’s original, accepted manuscript or the publisher’s version. / La version de cette publication peut être l’une des suivantes : la version prépublication de l’auteur, la version acceptée du manuscrit ou la version de l’éditeur. Publisher’s version / Version de l'éditeur: American Railway Engineering Association Bulletin, 60, 549, pp. 669-688, 1959- 06-01 NRC Publications Record / Notice d'Archives des publications de CNRC: https://nrc-publications.canada.ca/eng/view/object/?id=e527d1fd-f59c-4f2d-b869-c5a022f4369b https://publications-cnrc.canada.ca/fra/voir/objet/?id=e527d1fd-f59c-4f2d-b869-c5a022f4369b Access and use of this website and the material on it are subject to the Terms and Conditions set forth at https://nrc-publications.canada.ca/eng/copyright READ THESE TERMS AND CONDITIONS CAREFULLY BEFORE USING THIS WEBSITE. L’accès à ce site Web et l’utilisation de son contenu sont assujettis aux conditions présentées dans le site https://publications-cnrc.canada.ca/fra/droits LISEZ CES CONDITIONS ATTENTIVEMENT AVANT D’UTILISER CE SITE WEB. Questions? Contact the NRC Publications Archive team at [email protected]. If you wish to email the authors directly, please see the first page of the publication for their contact information. Vous avez des questions? Nous pouvons vous aider. Pour communiquer directement avec un auteur, consultez la première page de la revue dans laquelle son article a été publié afin de trouver ses coordonnées. Si vous n’arrivez pas à les repérer, communiquez avec nous à [email protected]. 8er rHl N21t2 no. ?2 " c.2 BI,DG ] NerroNll ReseancH Couxctu CANADA DIVISION OF BUILDING RESEARCH ANALYZED SOIL ENGINEERINGPROBLEMS ON THE QUEBECNORTH SHORE AND LABRADORRAILWAY BY K. B. WOODS.R. W. J. PRYERAND W. J. EDEN REPRINTED FROM AMERIcAN RArLwAy ENGTNEERTNGAssocrATroN i{r*rrr.l, ppgc66}tN}es vol-. 60, NO. 549, FEBRUARY 1959. P. 669 - 644. TECHNICAL PAPER NO. 72 OF THE DIVISION OF BUILDING RESEARCH OTTAWA JUNE 1959 NRC 5t93 PRICE 25 CENTS -4G,C / ?4b Thls publlcatlon is belng dlstrtbuted bt the Dlvtslon of Bulldtng Research of the Natlonal Research Councll as a contributlon towards better bulldlng in Canada. It should not be reproduced ln whole or in part, without pernisslon of the orl- glnal publlsher. The Dlvlslon would be gLad to be of asstetance in obtaining such pertlsslon. Publlcatione of the Dlvlslon of Bul1dlng Research nay be obtalned by rnalllng the approprlate reurlttance, (a Bank, Express, or Post Office liloney 0rder or a cheque rnade payable at par ln Ottawat to the Receiver General of Canada, crsdlt Natl,ona1 Research Counctl) to the Natlonal Research Council, Ottawa. Stanps are not acceptable. A coupon sSrstem has been lntroduced to nake pa;ments for publlcatlons relatively elmple. Coupons are avallable ln denourlnatlons of 5, 25t and 50 cents, and may be obtaLned by uraklng a re- nrlttance as lrdlcated abore. These coupons rnay be used for the purchase of all National Besearch Councll- pubLLcatlons includlng speclflcatlons of the Canadian GorrerrunentSpeciflcatlons Board. il1il ullillil t'r Roadway and Ballast 669 Soil Engineering Problems on the Quebec North Shore & Labrador Railway By K. B. Woods,* R. W. J. Pryer,x* W. J. Eden*** A. SYNOPSIS The construction of a 360-mile railroad to reach the iron-ore deposits in Quebec- Labrador in terrain virtually unknown could be expected to r,aiseserious problems with respect to soil conditions. The climate of the region imposed another set of difEculties because the winters are severe and the short summer season is cool with frequent rain- fall. This paper points out the diffrculties that w,ere caused by soil conditions and sets forth some of the measures taken to remedy the situation. slope stability in banded clays was a serious problem in the fust 30 miles. Because of the climabe, frost action was a major consideration throughout the length of the line. construction problems were mainly caused by loose, saturated soils with very poor natural drainage, and frequent rainfall in the summer months. B. INTRODUCTION Few engineering projects in reoent years have matched the scale of the iron-ore development in Quebec-Labrador. A major phase of this undertaking was the con- struction of the Quebec North Shore & Labrador Railway between the rich iron-ore deposits of the Schefferville area and the tidewater docks at Sept Iles. This paper summarizes some of the soil engineering problems encountered in this undertaking and discusses methods used to solve the difficulties encountered. The railway, a single-track line, is based at tidewater 1 mile east of the town of Sept fles on the north shore of the Gulf of St. Lawrence, and some 484 miles northeast of Montreal. Schefferville (El. 1700), the northern terminus, is almost due north o,f Sept Iles, a distance of 358 miles by rail. The terrain traversed by the railway (Fig. t) may be describ,ed generally as the Laurentian Plateau of the Canadian Shield, but a number of different geological and soil formations are encountered, each one raising problems peculiar to the location. Reconnaissance and aerial surveys were undertaken in 1945 and 1946 (l)f and preliminary lines run during the following two years. rn 1949, optimum train lengths, weights and speeds having been established, final location surveys were begun. Con- struction commenced in late 1950 (2) and track laying was completed in February 1954. A total of 21 million cu yd of excavation was required,6 million cu yd being involved in the construction of haulage roads and 1l intermediate airstrips between those at Sept Iles and Schefferville. * Head, Civil Engineering Department, Purdue University. ** Soils engineer, Quebec North Shore & Labrador Railway. *x* Division of Building Reseach, Natioual Research Council, Cmada. t Numbers in paenthesis refer to references at end of report. I'l Roadway and Ballast 6Po I .\ Trt s / \ r..- -r. ^(,, I I I f I I \ I It&nihek Lole taaaaoon \ \: \i TROU6H , Mds L \,, LABRADOR Z.\ ( )t 200 \ \) LAKE ( t\ ( -PLATEAU AshrnipiAsh[l L! \\ *,-..a(' v.1 t1iY,r"ltl_,:- ^'t.) , \ \ t-. -5?. QUEBEC-- 5i- s:9- MPsO d [yy;YY-!*#!"i)- -, :_:7: 1.Qoi;o;v tl | 6tt'- Gulf of.l.uSt LowrenceI . of Fic.- -''r"il*-.y'(adapiea l-Physiographic-map -of L-abrador Peninsula_ showing-locat-ion |roi Canadian Geographer, No' 5' 1955' p' 9)' Roadway and Ballast 6?r 80 70 70 60 -.? 60 U E d- t _ F50 NOB LAKE 50 t tlj a40 40 2 lrJ F t( 50 >30 A\ t -J I F ^\ I ?20 20 g I t'. = ln I f ro ?ro , =U $.t o \ EVEIltsL NOS- -to -to o J -20 -20 t2 MEAN MONTHLYTOTAL PRECIPITATION ( INCHES} SEVEN ISLANDS LAT. 50" - lO N LONG.660- l5 W ( rr veras REcoRos) KNOBLAKE LAT. 54" - 40N LONG.669- 55 W t royEARs REcoRos ) Fig. 2-Composite hythergraph of Knob Lake and Seven Islands. C. CLIMATE The climate of the region varies f rom maritime at sept Iles to sub-arctic at schefferville (3). Fig 2 shows hythergraphs for schefferviltre and Sept Iles by which lhe climates may be compared in terms of mean monthly temperature and precipitation. The coastal region is one of relatively high precipitation, the average annual p.".ipit"tiott at Sept Iles being 42 in. The heaviest monthly rainfall is close to 6 in and occurs generally in July. A second peak of precipitation occurs during the winter months when saturated air from the Gulf of St. Lawrence comes into contact with the steep slopes of the north shore. Annual snowfall is of the order of 170 in, while the heaviest monthly snowfall averages 50 in and occurs usually in January. On the Labrador Plateau (or in the region north of Mile Post 100) precipitation is more moderate. At Schefferville, the average annual precipitatiOh is 28 in, of which rainfall olz Roadway and Ballast accounts for slightly more than one-half. The heaviest monthly rainfall amounts to 3.5 in and occurs in J,uly and August, the only months during which snowfall is neg- ligible. Annual snowfall is approximately 130 in, most of which is fairly evenly dis- tributed over the months from October to April. By way of further comparison, Sept Iles has temperature conditions. comparable with Regina, Sask., and Schefferville with Dawson in the Yukon Territory. Both Sept Iles and Regina have mean average annual temperatures of 34 deg F, while the cor- responding figure for Schefferville and Dawson is 23 deg F. The Quebec-Labrador area, however, does not experience the wide range from midwin'ter low to midsummer high temperatures common to both Regina and Dawson. The comparison cannot be extended to include precipitation; the annual precipitation at Sept IIes being almost three times that at Regina, and the annual precipitation at Schefferville more than twice that at Dawson. D. VEGETATION In the upland region south of M.P. 100, heavy precipitation, a cool climate and sandy soil have contributed to the development of a mixed coniferous and deciduous Iorest type of vegetatlon with spruce, balsam fir, and tamarack as the dominant species of tree. Birch is the principal hardwood. Poorly diained areas, lakeshores and the banks of streams support thickets of willow and alder. The forest floor is generally leatured by a dense growth of ericaceous shrubs such as the Labrador Tea plant and blueberry which thrive upon the acid, humus soil. A ground cover of moss, lichens and fungi with some ferns and grasses has developed upon a relatively deep deposit of partially decomposed woody vegetable debris.