Field loading tests on muskeg

Field loading tests on muskeg

14A iii BURLAND, JB BUILDING RESEARCH STATION, WATFORD, GB MOORE,JF BUILDING RESEARCH STATION, WAT~YSRD,GB The measurement of ground displacement aro...

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iii BURLAND, JB BUILDING RESEARCH STATION, WATFORD, GB MOORE,JF BUILDING RESEARCH STATION, WAT~YSRD,GB The measurement of ground displacement around deep excavations. In Field Instrumentation in Geotech. Engng.Proc. Symposit~n BGS, May 1973. 14F,4R. B~,'I'mmgORTHS,LONDON, 1973, P70-84. The paper describes types of movements around excavations and a variety of equipment and measurement techniques used in monitoring. The most effective base for surveying instrt~nents is datum pillar; inclinometers are used for measuring the inclination of a borehole at various depths; magnet extensometers are used in horizontal, vertical and inclined boreholes; the micrometer rod is helpful when displacements around excavations occur under approximately plane strain conddtions e.g. behind a long diaphragm wall. The methods given in the paper have been developed as a result of experience gained on construction sites. 112 MARSLAND, A BUILDING RESEARCH STATION WATFORD, GB EASON, BJ BUILDING RESEARCH STATION WATFORD, GB Measurement of displacements in the ground below loaded plates in deep boreholes. In Field Instrumentation in Geotech.Engng.Proc. Symposium BGS, 1973. 7F, IT, 9R. BUITEEWORTHS, LONDON, 1973, P304-317. Equipment has been developed for measuring displacement in the ground below large diameter plate loading tests. This equipment can be quickly installed in s confined space at the bottom of a 900 m. borehole. Typical measurements obtained using this equil~nent are given.

113 BOSMAN, HC COMINC0 LTD.TRAIL, B. C. CDN Mine evaluation and production scheduling -MEPS. -Description of system of Fortran programs for use in mining, and examples of its usage. 9F. CAN. INST.MIN.METALL. BULL.V66, N734,1973, P92-97.

Surface structures See also abstract: 209. 114 ELLIE, G CHARBONNAGES DE FRANCE, PARIS, F TERVO, R MINEs BR. DEPY. EN. MIN. RES. O~YARIO, CDN Televigile. An automated system for remote surveillance and information gathering in mines. CAN. INST. MIN. METALL. BULL.V66, N736,1973, PI60-165. i15 BEVAN, PA LA LUZ MINES LTD.NIC Roslta mine. A brief history amd geological description. 3F, IT,3R. CAN. INST.MIN.M~TALL. BULL.V66, N736, i~73, P60-84. The general location, topography and climate are discussed briefly, together with an historical record of the deposit (copper, silver, gold). General geology, grade control arg ore reserves are covered at some lemgth, and reasons are given for the operation being placed on a salvage basis. Auth.

AUTHOR AND SUBJECT INDEXES TO EACH YEARS EDITIONS OF GEOMECHANICS ABSTRACTS WILL BE INCLUDED IN THE DECEMBER ISSUE. MONTHLY INDEXES WILL NOT BE PUBLISHED.

Embankments and embankment dams See also abstract: 176. i16 HOLLINGSHEAD, GW ROYAL MILITARY COIl. KINGSTON, ON2. CDN RAYMOND, GP QUEENS UNIV, KINGSTON, ONTARIO, CDN Field loading tests on muskeg. 17F,4T,14R. CANAD. GEOTECH. J.Vg, N3,19~2,P278- 289. Results of tests performed using a 1.8-m(6-ft) diameter flexible based tank capable of being filled with 3.6m (12ft) of water are presented. Two series of tests were performed on a muskeg with an undrained shear strength of 5-7.SkN/m2(100-1501b/sq.ft). The first consisted of filling the tank alone and the second with the tank positioned at the centre of a 4.5-m (15-ft) diameter 0.6m(2ft) high flexible based reservoir. The results thus simulate the comparison of the effect of berms on the stability of embankments. Consideration is given to the short term effect of berms where they are constructed rapidly at the same time as t h e central fill and the long term effect where they and the central fill are constructed slowly. The resulting vertical movements were measured using a torpedo settlement gauge. The horizontal movements were measured using an inclinometer as well as a [email protected] m o ~ m ~ r ~ device. The pore pressures were measured uslng fine stoned piezometers Laboratory tests were conducted to compare predicted a.r~ measured results. Auth.

~MSON, L TERRATL~H LTD. MONTREAL, CDN L~ ROC}~WI ~, P UNIV. LAVAL, QUEBEC, CDN Design and performance of an expressway constructed over peat by preloadir~g. 15F, 2T, lOR. CANAD. GEGTECH. J.vg, ~ , 1972, P447-466. %~qis paper presents the complete record of the laboratory investigations a n d field observations made An conjunction with the construction of expressway embankments built by preloading over a muskeg. Laboratory ~md field tests were performed before and during construction. Field vane tests made at the end of preloading stage indicated a considerable gain in t h e shear ,~tremgth as result of consolidation. Compressibility characteristics of the peat measured in the labaratory are compared with the field behaviour. Periodical field level observations were taken during 4 years after the removal of the temporary surcharge and have shown that t~e highway embankments heaved 2-3in. (5.0-7.5cm) over a period of 12 months at a gradually decreasing rate. The rebound was followed by long-term secondary settlements. Analysis of the settlement records shcws that preloading has been beneficial in reducir~ the coefficient of secorzlary compression of the peat. Preloading was simulated in the laboratory by means of oedometer tests on peat samples; both the laboratory results and the field observations revealed a remarkable agreement between the duration of the surcharga stage and the ti1~ for rebound to be complete after removal of the s~charge. Auth.

BISHOP, AW GREEN, PA

IMPER. COI.L. SCI. TECHNOL. LONDON, G~

The development and use of trial embankments. In Field Instrumentation in Geotech.Engng.Proc. Symposium BGS, May 1973. 6F, BT,61R. BD['±'~h~ORTHS,LONDON, 1973, P13-37. Yn this paper increased emphasis has been given to instrumented trial e m b a n ~ n t s . While every published record of an instr~mnted tri~l bank or working structure may reduce the need for another trial embank~.ent under similar circumstar~es, the near future is likely to see an i~crease in their effective economic use under a wide range of site condltions. The variability along the centre-line of the long embankments which most clearl~ Justify their use mu~t not be overlooked; nor ~ t the fact that short-term