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Geotechnical properties of the Corinth Canal marls
t 0A quoted in recent work are drained and undrained moduli and Poisson's ratio, pore and grain compressibility, effective stress pore pressure (Skempton) parameter. Darcy conductivity, and hydraulic diffusivity. The parameters are considered with reference to the Rice and Cleary (1976) formulation for poroelasticity. References to Blot's parameters are given for completeness. Extensions to the basic theory are presented. 921069 Behaviour of offshore soils containing gas bubbles Sills, G C; Wheeler, S J; Thomas, S D: Gardner, J N Geotechnique I"41. N2, June 1991, P227-24l Results of an extensive laboratory examination of reconstituted soil samples containing bubbles are reviewed. The medium is, in effect, gas filled cavities surrounded by a matrix of saturated soil. Surface tension effects limit overall difference between gas pressure and pore water pressure. Overall void volume is effectively a function of matrix strength, and void volume changes can be modelled using cavity expansion theory. A new parameter, operative stress (total stress minus pore water pressure), is seen to influence consolidation and strength behaviour of these soils. The presence of bubbles has significant effects on acoustic properties of fine grained offshore soils. 92 ! 070 Improved technique for estimation of preconsolidation pressure. Technical note Sridharan. A; Abraham, B M; Jose, B T Geotechnique 1/41, N2, June 199l, P263-268 Accurate determination of preconsolidation pressure is important to prediction of long term consolidation and short term stability. Sample disturbance, test procedures in obtaining the compression curve, environmental factors, and interpretation techniques can all influence the computed value of preconsolidation pressure. An improved method to determine preconsolidation pressure, based on logarithmic plot of (l + void ratio) against effective pressure is proposed. Comparison against the Casagrande method is illustrated for a range of cohesive soils. 921071 Geotechnical properties of the Corinth Canal marls Anagnostopoulos, A G; Kalteziotis, K; Tsiambaos, G K; Kavvadas, M Geotech GeM Engng V9, NI, March 1991. P1-26 Only minor slope stability problems have occurred along the Corinth Canal,despite steep angles and regional seismicity, A laboratory program to investigate these bluish grey Corinth marls was undertaken. Results show the intact material is stiff, brittle, with high apparent cohesion at low to moderate stress levels, resulting from carbonate cementation. The material yields with gradual bond degradation. Remoulded samples have comparable residual strength, but lower pre-yield stiffness and peak strength. 921072 Fitting strength criteria to intact rock Carter, B J; Scott Duncan, E J; Lajtai, E Z Geotech GeM Engng II9, NI, March 1991, P73-8t Rock strength data covering the full range of stress conditions are presented for Lac du Bonnet granite, limestone (Tyndallstone), and Prairie Evaporite potash rock. Hoek and Brown and Johnston failure criteria are fitted to the strength data for
about 500 laboratory tests using the PC code ROCKER. A third parameter is included in the Hoek and Brown criterion to account for the low tensile strength of the salt rock A nev,~ simple criterion, the Rocker function, is formulated to follo~ the strength data closely in the tension-low confining pressure region. 921073 Influence of schistosity on the strength and wave velocity characteristics of a mica schist saprolite Ogunsanwo, O lnt Assoc Engng Geol Bull N43, April 1991, P75-79 Undisturbed samples of schist saprolite were taken in an area near llesha,south west Nigeria. Anisotropy of unconfined compressive strength and wave velocity with respect to inclination of schistosity planes was examined for each set of sampies. Microfabric studies were used to explain differences between sample sets. Relevance to soil classification studies and site investigation is discussed. 92 ! 074 Relationships between post-failure state and compression strength of Sudetic fractured rocks Pininska, J; Lukaszewski, P lnt Assoc Engng GeM Bull N43. April 1991, P81-86 Cylindrical samples of rock with variable states of metamorphism and of variable faulting and fracturing with secondary mineralisation were tested at constant deformation rate in a servo controlled testing machine. Pre- and post-failure critical fracture energy effects are discussed. Regression analysis is used to determine a correlation between residual strength and standard compression strength. 921075 Thermomechanical analysis of the G-Tunnel heated block experiment using a compliant-joint rock-mass model Costin, L S; Chen, E P Int J Num Anal Meth Geomech V15, N6. June 1991. P379398 Results of two dimensional finite element simulations of several thermal/mechanical loading cycles of a block of jointed welded tuff are presented. The finite element codes JAC and COYOTE were used, and a compliant joint constitutive model of Chen (1989). Output is compared to experimental data (Zimmerman et al, 1986). Qualitative agreement is seen in all cases, quantitative agreement in some. 921076 Micromechanical-based bipolar theory for deformation of granular solids Chang, C S; Ma, L Int J Solids Struct V28, NI, 1991, P67-86 An equivalent continuum model of a granular material is presented in which particle translation and rotation are treated as two independent continuum fields. A generalised measure of strain is developed consisting of deformation strain resulting from particle translation and polar strain resulting from rotation. The stress measure correspondingly consists of both Cauchy and polar stresses. Using the derived constitutive taw and field equations, a procedure based on finite element analysis is used to solve boundary value problems. Results are compared to those of distinct element analysis. No sliding, separation, or rearrangement of particles is included in this analysis.
© 1992 Pergamon Press plc. Reproduction not permitted
about 500 laboratory tests using the PC code ROCKER. A third parameter is included in the Hoek and Brown criterion to account for the low tensile strength of the salt rock A nev,~ simple criterion, the Rocker function, is formulated to follo~ the strength data closely in the tension-low confining pressure region. 921073 Influence of schistosity on the strength and wave velocity characteristics of a mica schist saprolite Ogunsanwo, O lnt Assoc Engng Geol Bull N43, April 1991, P75-79 Undisturbed samples of schist saprolite were taken in an area near llesha,south west Nigeria. Anisotropy of unconfined compressive strength and wave velocity with respect to inclination of schistosity planes was examined for each set of sampies. Microfabric studies were used to explain differences between sample sets. Relevance to soil classification studies and site investigation is discussed. 92 ! 074 Relationships between post-failure state and compression strength of Sudetic fractured rocks Pininska, J; Lukaszewski, P lnt Assoc Engng GeM Bull N43. April 1991, P81-86 Cylindrical samples of rock with variable states of metamorphism and of variable faulting and fracturing with secondary mineralisation were tested at constant deformation rate in a servo controlled testing machine. Pre- and post-failure critical fracture energy effects are discussed. Regression analysis is used to determine a correlation between residual strength and standard compression strength. 921075 Thermomechanical analysis of the G-Tunnel heated block experiment using a compliant-joint rock-mass model Costin, L S; Chen, E P Int J Num Anal Meth Geomech V15, N6. June 1991. P379398 Results of two dimensional finite element simulations of several thermal/mechanical loading cycles of a block of jointed welded tuff are presented. The finite element codes JAC and COYOTE were used, and a compliant joint constitutive model of Chen (1989). Output is compared to experimental data (Zimmerman et al, 1986). Qualitative agreement is seen in all cases, quantitative agreement in some. 921076 Micromechanical-based bipolar theory for deformation of granular solids Chang, C S; Ma, L Int J Solids Struct V28, NI, 1991, P67-86 An equivalent continuum model of a granular material is presented in which particle translation and rotation are treated as two independent continuum fields. A generalised measure of strain is developed consisting of deformation strain resulting from particle translation and polar strain resulting from rotation. The stress measure correspondingly consists of both Cauchy and polar stresses. Using the derived constitutive taw and field equations, a procedure based on finite element analysis is used to solve boundary value problems. Results are compared to those of distinct element analysis. No sliding, separation, or rearrangement of particles is included in this analysis.
© 1992 Pergamon Press plc. Reproduction not permitted