- Email: [email protected]
High penetration C3S bentonite-cement grouts for finely fissured and porous rock
81A
892244 Simple techniques of ground improvement with cement Greenwood, D A Proc int Conference on Foundations and Tunnels, London, 2426 March 1987 V2. P8-19. Publ Edinburgh: Engineering Technics Press, 1987 Soil stabilisation requires a high degree of uniform particle bonding, for which cementitious grout may be used. The grout may be introduced by injection or mixing. Permeation, soil displacement and mix in place methods are discussed, showing that permeation by cements is impracticable in most soils, but injection to displace the soil fabric and mixing to destroy it allow cement to be introduced into the soil. This understanding is applied to engineering use, using compaction grouting, squeeze grouting, grout jacking, jet grouting and mechanical mixing as examples.
892245 Deep consolidation using the jet-grouting system for the tunnels and bottom plug of the Presenzano hydroelectric power plant - execution and checks Bertero, M; Paviani, A; Vanni, D Proc lnt Conference on Foundations and Tunnels, London, 2426 March 1987 V2, P20-28. Publ Edinburgh: Engineering Technics Press, 1987 Jet grouting is used to improve soil properties by incorporating stabilising agents by means of hydraulic mixing. The method was used during construction of the Presenzano hydroelectric plant to improve earth at the foot of temporary diaphragm walls and consolidate soil around tunnel excavation sites. Use of the kajima method columnar treatment, checking the vertical alignment of holes and choice of drillhole centre distance for jet-grouting treatment are discussed. 892246 High penetration C3S bentonite-cement grouts for finely fissured and porous rock Gandais, M; Delmas, F Proc int Conference on Foundations and Tunnels, London, 2426 March 1987 V2, P29-33. Publ Edinburgh: Engineering Technics Press, 1987 By adding bentonite to cement grouts, stability is increased and a water retention potential, which affects the loss of water by filtration under pressure, is modified. Tests were conducted to quantify the filtration effect and showed that a pasty deposit develops at the filtration surface. Dispersing agents were used to reduce this growth and therefore increase the penetration ability of the grouts. The new grout, C3S, fills a larger proportion of the voids with no change in grouting parameters, particularly grouting pressure. Application of C3S at 2 damsites is described.
strain can be easily evaluated. CBR (puncture) test values are presented for a variety of textiles, membranes, nets and composites, and compared to values from wide width tension tests. The new test may be used as an index test for geosynthetics.
892248 Strength evaluation of geotextiles Venkatappa Rao, G; Pandey, S K Indian Geotech J VI7, N4, Oct 1987, P301-323 Geotextiles are widely used in civil engineering for separation, filtration, reinforcement and drainage. The variety of burst resistance, puncture resistance, narrow and wide strip tensile tests and cone drop tests used is reviewed. Three woven polypropylene fabrics were evaluated using these tests. Correlations between test results are discussed. The tests are seen to be simple to use, reproducible and easily standardised.
892249 Strength characteristics of soil reinforcement Mandal, J M Indian Geotech J VI7. N4, Oct 1987, P324-333 Stress strain behaviour of reinforced earth under different moisture contents and with different type and form of reinforcing element has been studied. Conventional triaxial tests were carried out on 38ram diameter by 76mm high soil specimens containing either 0.5 or 2.0% of mild steel fibres or 2 or 3 (0.2 or 0.3%) aluminium discs of diameter 25ram. Specimen preparation is described. Results indicate that type and form of reinforcement influences strength, and that placement dry of optimum moisture content is advantageous for compacted fills of cohesive reinforced soils. 892250 Pull-out behaviour of polymer grid in soils and its analytical method Ochiai, H; Hayashi, S, Otani, J; Sakai, A, Ogisako, E; Sato, K Mere Fac Engng Kyushu Univ V48, N2, June 1988. P125-139 Grid displacement and mobilisation of pullout resistance were investigated for reinforced sand and Masa (weathered granite) soils in a transparent soil box. An expression relating pullout resistance to normal stress and cohesion and friction angle of the soil is developed. Finite element analysis using a Goodman type joint element was used to model the pullout tests. The predicted development of pullout resistance with grid displacement is in good agreement with observed results.
Soil stabUisation 892251 Experience with building construction and operation by the permafrost soil stabilization method Khrustalev, L N; Nikiforov, V V; Gorbacheva, V M Soil Mech Found Engng V24, NS, Sept-Oct 1987, P181-184
Reinforced earth See also: 892345 892247 CBR strength (puncture) of geosynthetics Murphy, V P; Koerner, R M Geotech Test J VII, N3, Sept 1988, P167-172 A simple test in which a 50mm diameter plunger is forced through a horizontally fixed synthetic of 150ram diameter is described. These dimensions are common to the California Bearing Ratio test apparatus. The test is an axisymmetric strength test, rather than a strict puncture test. Stress and
This method is used in areas where the seasonal freezing layer does not connect with the permanent permafrost layer, and permafrost soils are highly compressible on thawing and surface soils are subject to frost heave. By use of a ventilated cellar, the top of the permafrost layer is maintained at an originally specified layer at all times. A mean long term air temperature close to 0 deg C is maintained in the cellar, and depth of seasonal thaw and seasonal freezing are the same. A thermal curtain is maintained between the surface layers and permafrost.
© 1989 Pergamon Press plc. Reproduction not permitted
892244 Simple techniques of ground improvement with cement Greenwood, D A Proc int Conference on Foundations and Tunnels, London, 2426 March 1987 V2. P8-19. Publ Edinburgh: Engineering Technics Press, 1987 Soil stabilisation requires a high degree of uniform particle bonding, for which cementitious grout may be used. The grout may be introduced by injection or mixing. Permeation, soil displacement and mix in place methods are discussed, showing that permeation by cements is impracticable in most soils, but injection to displace the soil fabric and mixing to destroy it allow cement to be introduced into the soil. This understanding is applied to engineering use, using compaction grouting, squeeze grouting, grout jacking, jet grouting and mechanical mixing as examples.
892245 Deep consolidation using the jet-grouting system for the tunnels and bottom plug of the Presenzano hydroelectric power plant - execution and checks Bertero, M; Paviani, A; Vanni, D Proc lnt Conference on Foundations and Tunnels, London, 2426 March 1987 V2, P20-28. Publ Edinburgh: Engineering Technics Press, 1987 Jet grouting is used to improve soil properties by incorporating stabilising agents by means of hydraulic mixing. The method was used during construction of the Presenzano hydroelectric plant to improve earth at the foot of temporary diaphragm walls and consolidate soil around tunnel excavation sites. Use of the kajima method columnar treatment, checking the vertical alignment of holes and choice of drillhole centre distance for jet-grouting treatment are discussed. 892246 High penetration C3S bentonite-cement grouts for finely fissured and porous rock Gandais, M; Delmas, F Proc int Conference on Foundations and Tunnels, London, 2426 March 1987 V2, P29-33. Publ Edinburgh: Engineering Technics Press, 1987 By adding bentonite to cement grouts, stability is increased and a water retention potential, which affects the loss of water by filtration under pressure, is modified. Tests were conducted to quantify the filtration effect and showed that a pasty deposit develops at the filtration surface. Dispersing agents were used to reduce this growth and therefore increase the penetration ability of the grouts. The new grout, C3S, fills a larger proportion of the voids with no change in grouting parameters, particularly grouting pressure. Application of C3S at 2 damsites is described.
strain can be easily evaluated. CBR (puncture) test values are presented for a variety of textiles, membranes, nets and composites, and compared to values from wide width tension tests. The new test may be used as an index test for geosynthetics.
892248 Strength evaluation of geotextiles Venkatappa Rao, G; Pandey, S K Indian Geotech J VI7, N4, Oct 1987, P301-323 Geotextiles are widely used in civil engineering for separation, filtration, reinforcement and drainage. The variety of burst resistance, puncture resistance, narrow and wide strip tensile tests and cone drop tests used is reviewed. Three woven polypropylene fabrics were evaluated using these tests. Correlations between test results are discussed. The tests are seen to be simple to use, reproducible and easily standardised.
892249 Strength characteristics of soil reinforcement Mandal, J M Indian Geotech J VI7. N4, Oct 1987, P324-333 Stress strain behaviour of reinforced earth under different moisture contents and with different type and form of reinforcing element has been studied. Conventional triaxial tests were carried out on 38ram diameter by 76mm high soil specimens containing either 0.5 or 2.0% of mild steel fibres or 2 or 3 (0.2 or 0.3%) aluminium discs of diameter 25ram. Specimen preparation is described. Results indicate that type and form of reinforcement influences strength, and that placement dry of optimum moisture content is advantageous for compacted fills of cohesive reinforced soils. 892250 Pull-out behaviour of polymer grid in soils and its analytical method Ochiai, H; Hayashi, S, Otani, J; Sakai, A, Ogisako, E; Sato, K Mere Fac Engng Kyushu Univ V48, N2, June 1988. P125-139 Grid displacement and mobilisation of pullout resistance were investigated for reinforced sand and Masa (weathered granite) soils in a transparent soil box. An expression relating pullout resistance to normal stress and cohesion and friction angle of the soil is developed. Finite element analysis using a Goodman type joint element was used to model the pullout tests. The predicted development of pullout resistance with grid displacement is in good agreement with observed results.
Soil stabUisation 892251 Experience with building construction and operation by the permafrost soil stabilization method Khrustalev, L N; Nikiforov, V V; Gorbacheva, V M Soil Mech Found Engng V24, NS, Sept-Oct 1987, P181-184
Reinforced earth See also: 892345 892247 CBR strength (puncture) of geosynthetics Murphy, V P; Koerner, R M Geotech Test J VII, N3, Sept 1988, P167-172 A simple test in which a 50mm diameter plunger is forced through a horizontally fixed synthetic of 150ram diameter is described. These dimensions are common to the California Bearing Ratio test apparatus. The test is an axisymmetric strength test, rather than a strict puncture test. Stress and
This method is used in areas where the seasonal freezing layer does not connect with the permanent permafrost layer, and permafrost soils are highly compressible on thawing and surface soils are subject to frost heave. By use of a ventilated cellar, the top of the permafrost layer is maintained at an originally specified layer at all times. A mean long term air temperature close to 0 deg C is maintained in the cellar, and depth of seasonal thaw and seasonal freezing are the same. A thermal curtain is maintained between the surface layers and permafrost.
© 1989 Pergamon Press plc. Reproduction not permitted