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Mineral aggregate from lead mine tailings
46A simulation of embankment behaviour for 3 grout materials indicated that use of the new material resulted in a reduction of settlement to less than half that expected for a conventional jet grout. 931346 Sealing characteristics of selected grouts for water wells Edil, T B; Chang, M M K; Lan, L T; Riewe, T V Ground Water V30, N3, May-June 1992, P351-361 Groundwater supply and monitoring wells must be protected from contamination from formation waters of the strata through which they pass. Annular space grouts around the well casing are used to this effect. Laboratory evaluation of a series of grout materials is described. A model well was constructed in a sand-filled plexiglas container. Bentonite drilling mud containing various amounts of formation material, neat cement, powder and granular bentonite, and a bentonite slurry (Ohio mix) were evaluated. Finite element seepage analysis of the well experiments was used to assist in interpretation of results. 931347 Jet grouting - soil improvement case histories Koelling, M; Ringen, A Proc 28th Symposium on Engineering Geology and Geotechnieal Engineering, Boise, 1-3 April 1992 P73-83. Publ Pocatello: Idaho State University, 1992 In recent years, jet grouting, a replacement technique, has become an economic and technical alternative to more conventional construction methods. It finds applications in underpinning, excavation support, and groundwater control. Jet grouting systems and methods and the range of soils in which it may be used are described. Three case histories of its use are presented: cofferdam construction in Hawaii; underpinning, support and groundwater control during expansion of water treatment plant in Seattle; and underpinning an inadequately supported structure in California.
Reinforced earth See also: 931377, 931409, 931435 931348 Durability and creep of Texsol Blivet, J C; Leflaive, E Bull Liaison Lab Ponts Chaussees N178, March-April 1992, P27-33 Long term behaviour of Texsol, polymer filament reinforced soil, is discussed. To date, polyester fibre has been used for reinforcement. Provided soil pH is less than 10 (almost all natural soils), no physicochemical degradation will occur. Similarly, there is no evidence of bacterial deterioration of polyester. Observations of Texsol structures indicate lixiviation of surface particles by heavy rain, but this stabilises at depth 10-20mm. Laboratory accelerated creep tests over 3 years show no excessive deformation. 931349 Pullout stiffness of elastic anchors in slope stabilization systems Hryciw, R D; Irsyam, M J Geotech Engng Div A S C E Vl18, N6, June 1992, P903-919 Anchored geonets or geogrids may be used to stabilise soil slopes. Their effectiveness depends largely on tension remaining in the geosynthetic after installation. Pullout forces exerted
by the tensioned lhbric can lead to upward displacement of thc anchor-fabric connector, with loss of tension in the geosynthetic. The role of thc connector is examined and found to be crucial. Two alternatives to the pinned anchor are presented, spring-steel collar and threaded-anchor-and-nut connectors, which minimise tension loss. Theoretical solutions governing pullout mechanisms of anchors in cohesionless soil are developed.
931350 Pullout tests using steel grid reinforcements with low-quality backfill Bergado, D T; Lo, K H; Chai, J C; Shivashankar, R; Alfaro, M C; Anderson, L R J Geotech Engng Div A S C E Vl18, N7, July 1992. P10471063 Large scale laboratory tests and full scale field tests were used to characterise the pullout resistance of steel grids in three low quality cohesive/frictional backfill materials available in Thailand, clayey sand,lateritic soil, and weathered clay. Mobilised field pullout resistance and reinforcement strains were strongly influenced by the response of the wall/embankment system to subsoil movement and arching effects. Laboratory tests provided a conservative approximation of field observations and could be reasonably simulated by finite element analysis.
Soil stabilisation 931351 Geotechnical properties of a chemically stabilised soil from Malaysia with rice husk ash an additive All, F H; Adnan, A; Choy, C K Int J Geotech Geol Engng VIO, N2, June 1992, Pl17-134 Rice husk ash (RHA) is a widely available waste product in many tropical areas. It consists mainly of silica. Its application in addition to cement or lime to stabilise a residual granitic soil is described. Results are presented of compaction and strength tests of soils with different amounts of RHA and cement/lime. Durability of the stabilised soil to wet/dry cycling was also examined. Lime is a more effective stabilising agent than cement for this soil. Additions of RHA enhance both the strength and durability of the lime-stabilised soil. It may therefore be used to lower construction costs and alleviate the waste disposal problem.
931352 Mineral aggregate from lead mine tailings Zatler-Zupancic, B
Proc 6th International Congress International Association of Engineering Geology, Amsterdam, 6-10 August 1990 V4, P3209-3213. Publ Rotterdam: A A Balkema, 1990 Many millions of tonnes of lead-zinc mine tailings are available at Zerjav in Yugoslavia. They are composed mainly of sandstone and dolostone in the size range 4-45mm. Chemical and mineralogical analysis of the waste has been carried out, with attention paid to non-carbonate components. Various gradings were prepared by sieving, and sand by sieving and crushing. Cement stabilisation has been investigated. Results suggest the material may be used as aggregate in cement or asphalt mixes, but care must be taken to ensure Zn, Pb, and S contents are within allowable limits.
© 1993 Pergamon Press Ltd. Reproduction not permitted
Reinforced earth See also: 931377, 931409, 931435 931348 Durability and creep of Texsol Blivet, J C; Leflaive, E Bull Liaison Lab Ponts Chaussees N178, March-April 1992, P27-33 Long term behaviour of Texsol, polymer filament reinforced soil, is discussed. To date, polyester fibre has been used for reinforcement. Provided soil pH is less than 10 (almost all natural soils), no physicochemical degradation will occur. Similarly, there is no evidence of bacterial deterioration of polyester. Observations of Texsol structures indicate lixiviation of surface particles by heavy rain, but this stabilises at depth 10-20mm. Laboratory accelerated creep tests over 3 years show no excessive deformation. 931349 Pullout stiffness of elastic anchors in slope stabilization systems Hryciw, R D; Irsyam, M J Geotech Engng Div A S C E Vl18, N6, June 1992, P903-919 Anchored geonets or geogrids may be used to stabilise soil slopes. Their effectiveness depends largely on tension remaining in the geosynthetic after installation. Pullout forces exerted
by the tensioned lhbric can lead to upward displacement of thc anchor-fabric connector, with loss of tension in the geosynthetic. The role of thc connector is examined and found to be crucial. Two alternatives to the pinned anchor are presented, spring-steel collar and threaded-anchor-and-nut connectors, which minimise tension loss. Theoretical solutions governing pullout mechanisms of anchors in cohesionless soil are developed.
931350 Pullout tests using steel grid reinforcements with low-quality backfill Bergado, D T; Lo, K H; Chai, J C; Shivashankar, R; Alfaro, M C; Anderson, L R J Geotech Engng Div A S C E Vl18, N7, July 1992. P10471063 Large scale laboratory tests and full scale field tests were used to characterise the pullout resistance of steel grids in three low quality cohesive/frictional backfill materials available in Thailand, clayey sand,lateritic soil, and weathered clay. Mobilised field pullout resistance and reinforcement strains were strongly influenced by the response of the wall/embankment system to subsoil movement and arching effects. Laboratory tests provided a conservative approximation of field observations and could be reasonably simulated by finite element analysis.
Soil stabilisation 931351 Geotechnical properties of a chemically stabilised soil from Malaysia with rice husk ash an additive All, F H; Adnan, A; Choy, C K Int J Geotech Geol Engng VIO, N2, June 1992, Pl17-134 Rice husk ash (RHA) is a widely available waste product in many tropical areas. It consists mainly of silica. Its application in addition to cement or lime to stabilise a residual granitic soil is described. Results are presented of compaction and strength tests of soils with different amounts of RHA and cement/lime. Durability of the stabilised soil to wet/dry cycling was also examined. Lime is a more effective stabilising agent than cement for this soil. Additions of RHA enhance both the strength and durability of the lime-stabilised soil. It may therefore be used to lower construction costs and alleviate the waste disposal problem.
931352 Mineral aggregate from lead mine tailings Zatler-Zupancic, B
Proc 6th International Congress International Association of Engineering Geology, Amsterdam, 6-10 August 1990 V4, P3209-3213. Publ Rotterdam: A A Balkema, 1990 Many millions of tonnes of lead-zinc mine tailings are available at Zerjav in Yugoslavia. They are composed mainly of sandstone and dolostone in the size range 4-45mm. Chemical and mineralogical analysis of the waste has been carried out, with attention paid to non-carbonate components. Various gradings were prepared by sieving, and sand by sieving and crushing. Cement stabilisation has been investigated. Results suggest the material may be used as aggregate in cement or asphalt mixes, but care must be taken to ensure Zn, Pb, and S contents are within allowable limits.
© 1993 Pergamon Press Ltd. Reproduction not permitted