- Email: [email protected]
Influence of different vane types on undrained strength of soft Bangkok clay, Technical note
70A
902041 Properties of solid waste incinerator fly ash Poran, C J; Ahtchi-Ali, F J Geotech Engng Div ASCE VIIS, NS, Aug 1989, PIll81133 Engineering properties of solid waste incinerator fly ash were studied to evaluate its potential for use as compacted fill or for road and subbase construction. Moisture-density relations, permeability, shear strength, and California Bearing Ratio were measured. Effects of densification and stabilisation with lime or cement were also investigated. Cement stabilisation was very effective in reducing permeability and increasing shear strength and CBR, and this material is suitable for compacted fill or road subbases. Some environmental aspects of SWIF are discussed.
902042 Fissure parameters in stiff clays under compression Vallejo, L E J Geotech Engng Div ASCE VII5. N9, Sept 1989, P13031317 Laboratory tests were carried out to examine the effects of orientation, length, number, and pattern of fissures on unconfined compressive strength of stiff fissured clays. Prismatic samples of brittle kaolinite clay containing pre-existing fissures were used. Results indicate that there is a critical crack orientation at which UCS is a minimum. Increasing length and number of fissures lowers strength. Arrangement of fissures also influences behaviour. When testing fissured clays, large samples must be taken to ensure representative results.
902043 Crystal rotation by mechanical interaction between plastically anisotropic crystals Tharp, T M J Struct Geol VII, N5, 1989, P613-623 When polycrystalline minerals are deformed, minerals with plastic anisotropy may experience inhomogeneous deformation and interaction with neighbouring crystals. The effect of this on the development of preferred orientation has been studied using two dimensional finite element analysis of pure shear of a polycrystalline material with two identical orthagonal slip systems. The material is non-ductile in the yon Mises sense. Slip planes rotate towards a preferred orientation parallel to the maximum shear stress. Mechanical interaction produces this orientation by rigid body rotation of crystals not favourably oriented for slip.
902044 Effect of moisture content on mechanical properties of Nemo coal, Moberly, Missouri, U.S.A. White, J M; Mazurkiewicz, M Min Sci Technol vg, N2, Sept 1989, P181-185 Uniaxial compression tests were carried out parallel to and perpendicular to the bedding planes of samples of bituminous Nemo coal at room temperature and pressure. Water content of the coal samples was altered by careful soaking to the range 3.7-12.0"/o. Increase in water content resulted in decrease of Young's modulus and strength at failure, but the shape of the stress strain curve was little altered.
902045 Statistical processing of results of stabiiometer tests Bukhartsev, V N Soil Mech Found Engng V25, N6, Note-Dec 1988, P562-565 Strength parameters of soils, cohesion and friction angle, can be determined by direct shear or stabilometer tests. Stabilometers record principal normal stresses at the moment of specimen failure, and approximate test conditions to natural working conditions in structures and beds. A statistical analysis procedure to improve interpretation of stabilometer tests is presented.
902046 Evaluation of design parameters for soft clays as related to geological stress history Hanzawa, H Soils Found V29, N2, June 1989, P99-111 Soft clay deposits generally have long and complex histories. A classification method for soft clays, taking into account geological stress history, is first proposed. Coefficient of earth pressure at rest, Ko, is then discussed from the point of view of strength anisotropy variation with stress history. Undrained constitutive behaviour is considered in a similar manner. It is shown that proper understanding of geological stress history is vital in evaluating design parameters. A procedure for determining another important parameter, consolidation yield stress, on the basis of laboratory and field testing is presented.
902047 Elasto-plastic behavior of Ko-consolidated clay in torsion shear tests Hong, W P; Lade, P V Soils Found V29, N2. June 1989, PI27-140 The effect of principal stress rotation on constitutive behaviour was examined for Ko consolidated clay using torsional shear tests along various stress paths on hollow cylinder specimens. Prefailure behaviour was the characteristic most affected. The experimentally obtained failure surface could be modelled using an isotropic failure criterion. Coupling effects between stress and strain were seen when torsional shear and vertical normal stress were applied.
902048 Influence of different vane types on undrained strength of soft Bangkok clay. Technical note Kietkajornkul, C; Vasinvarthana, V Soils Found 1/29, N2, June 1989, P146-152 Soft Bangkok clay was tested using different shear vane types, type I without casing, type II in a preboring type hole. Undrained shear strengths were 20-30% greater when measured by type I, the difference being considered as dependent on sampling disturbance. Despite the large variation of plasticity of Bangkok clay, normalised type I strength based on Bjerrum (1972) and measured type II strength show a unique relation when plotted against overconsolidation ratio.
902049 Preliminary geotechnical characterization of pyroclastic rocks in Rionero in Vulture (Basilicata, Italy) Baldassarre, G; Radina, B; Cherubini, C Proe 1st International Symposium on Penetration Testing, ISOPT-1, Orlando,20-24 March 1988 VI, P329-333. Rotterdam: A A Balkema, 1988 Soils of the volcanic complex were examined. Borehole investigations showed three distinct units, thickly layered with blocks, thinly layered, and thickly layered, all with similar grain size distribution. The soils are medium dense to dense
1990 Pergamon Press plc. Reproduction not permitted
902041 Properties of solid waste incinerator fly ash Poran, C J; Ahtchi-Ali, F J Geotech Engng Div ASCE VIIS, NS, Aug 1989, PIll81133 Engineering properties of solid waste incinerator fly ash were studied to evaluate its potential for use as compacted fill or for road and subbase construction. Moisture-density relations, permeability, shear strength, and California Bearing Ratio were measured. Effects of densification and stabilisation with lime or cement were also investigated. Cement stabilisation was very effective in reducing permeability and increasing shear strength and CBR, and this material is suitable for compacted fill or road subbases. Some environmental aspects of SWIF are discussed.
902042 Fissure parameters in stiff clays under compression Vallejo, L E J Geotech Engng Div ASCE VII5. N9, Sept 1989, P13031317 Laboratory tests were carried out to examine the effects of orientation, length, number, and pattern of fissures on unconfined compressive strength of stiff fissured clays. Prismatic samples of brittle kaolinite clay containing pre-existing fissures were used. Results indicate that there is a critical crack orientation at which UCS is a minimum. Increasing length and number of fissures lowers strength. Arrangement of fissures also influences behaviour. When testing fissured clays, large samples must be taken to ensure representative results.
902043 Crystal rotation by mechanical interaction between plastically anisotropic crystals Tharp, T M J Struct Geol VII, N5, 1989, P613-623 When polycrystalline minerals are deformed, minerals with plastic anisotropy may experience inhomogeneous deformation and interaction with neighbouring crystals. The effect of this on the development of preferred orientation has been studied using two dimensional finite element analysis of pure shear of a polycrystalline material with two identical orthagonal slip systems. The material is non-ductile in the yon Mises sense. Slip planes rotate towards a preferred orientation parallel to the maximum shear stress. Mechanical interaction produces this orientation by rigid body rotation of crystals not favourably oriented for slip.
902044 Effect of moisture content on mechanical properties of Nemo coal, Moberly, Missouri, U.S.A. White, J M; Mazurkiewicz, M Min Sci Technol vg, N2, Sept 1989, P181-185 Uniaxial compression tests were carried out parallel to and perpendicular to the bedding planes of samples of bituminous Nemo coal at room temperature and pressure. Water content of the coal samples was altered by careful soaking to the range 3.7-12.0"/o. Increase in water content resulted in decrease of Young's modulus and strength at failure, but the shape of the stress strain curve was little altered.
902045 Statistical processing of results of stabiiometer tests Bukhartsev, V N Soil Mech Found Engng V25, N6, Note-Dec 1988, P562-565 Strength parameters of soils, cohesion and friction angle, can be determined by direct shear or stabilometer tests. Stabilometers record principal normal stresses at the moment of specimen failure, and approximate test conditions to natural working conditions in structures and beds. A statistical analysis procedure to improve interpretation of stabilometer tests is presented.
902046 Evaluation of design parameters for soft clays as related to geological stress history Hanzawa, H Soils Found V29, N2, June 1989, P99-111 Soft clay deposits generally have long and complex histories. A classification method for soft clays, taking into account geological stress history, is first proposed. Coefficient of earth pressure at rest, Ko, is then discussed from the point of view of strength anisotropy variation with stress history. Undrained constitutive behaviour is considered in a similar manner. It is shown that proper understanding of geological stress history is vital in evaluating design parameters. A procedure for determining another important parameter, consolidation yield stress, on the basis of laboratory and field testing is presented.
902047 Elasto-plastic behavior of Ko-consolidated clay in torsion shear tests Hong, W P; Lade, P V Soils Found V29, N2. June 1989, PI27-140 The effect of principal stress rotation on constitutive behaviour was examined for Ko consolidated clay using torsional shear tests along various stress paths on hollow cylinder specimens. Prefailure behaviour was the characteristic most affected. The experimentally obtained failure surface could be modelled using an isotropic failure criterion. Coupling effects between stress and strain were seen when torsional shear and vertical normal stress were applied.
902048 Influence of different vane types on undrained strength of soft Bangkok clay. Technical note Kietkajornkul, C; Vasinvarthana, V Soils Found 1/29, N2, June 1989, P146-152 Soft Bangkok clay was tested using different shear vane types, type I without casing, type II in a preboring type hole. Undrained shear strengths were 20-30% greater when measured by type I, the difference being considered as dependent on sampling disturbance. Despite the large variation of plasticity of Bangkok clay, normalised type I strength based on Bjerrum (1972) and measured type II strength show a unique relation when plotted against overconsolidation ratio.
902049 Preliminary geotechnical characterization of pyroclastic rocks in Rionero in Vulture (Basilicata, Italy) Baldassarre, G; Radina, B; Cherubini, C Proe 1st International Symposium on Penetration Testing, ISOPT-1, Orlando,20-24 March 1988 VI, P329-333. Rotterdam: A A Balkema, 1988 Soils of the volcanic complex were examined. Borehole investigations showed three distinct units, thickly layered with blocks, thinly layered, and thickly layered, all with similar grain size distribution. The soils are medium dense to dense
1990 Pergamon Press plc. Reproduction not permitted