Undrained Cyclic Shear Behaviour of Normally Consolidated Clay Subjected to Initial Static Shear Stress

Model of Soft Soils under Cyclic Loading

“…Factors influencing the cyclic performance of soft soils have been investigated: (i) cyclic stress level which determines whether the soil can reach a non-failure equilibrium state or not (Larew and Leonards 1962;Lashine 1971;Sangrey et al 1978;Ansal and Erken 1989;Zhou and Gong 2001), (ii) loading frequency which is responsible for the rate of excess pore pressure and axial strains (Takahashi et al 1980;Yasuhara at al. 1983;Procter and Khaffaf 1984;Hyde et al 1993;Liu and Xiao 2010), (iii) over-consolidation ratio influencing the effective stress paths and the degradation of the undrained secant shear modulus (Sangrey et al 1969;Brown et al 1975;Vucetic and Dobry 1988), and (iv) static pre-shearing which decreases the cyclic shear strength but increases the total shear strength (Seed and Chan 1966;Zimmie and Lien 1986;Ishihara et al 1993;Hyodo et al 1994). …”

“…Hyodo et al (1994) An exponential relationship for pore pressure against time was established and corresponding stability criteria were developed using the critical state line.…”

Study on Excess Pore Water Pressure Changes of Saturated Soft Clay Subjected to Undrained Uni-Directional and Multi-Directional Cyclic Simple Shears

“…Dưới tác động của tải trọng động, đất loại sét (kể cả đất sét yếu) có sức kháng động tốt hơn đất loại cát [4] nên các nghiên cứu về tính chất động học của đất nền chủ yếu tập trung trên đất cát [14]. Tuy nhiên, kết quả quan trắc thực tế cho thấy lực cắt trượt động của sóng S (sóng ngang) trong động đất gây tăng nhanh áp lực nước lỗ rỗng và làm giảm sức kháng cắt của đất nền.…”

Behaviour of MH silts with varying plasticity indices

“…The test outcomes demonstrated that undisturbed and reconstituted samples behaved similarly in terms of deviator stresses and stress paths. Hyodo et al (1994) added that the ageing effects such as chemical bonding or secondary compression for undisturbed samples were eliminated during the application of effective confining stress to the normally consolidated state during the consolidation stage. Therefore, the work of Hyodo et al (1994) guaranteed that the behaviour of normally consolidated undisturbed samples can be decently depicted by reconstituted samples.…”

“…In a different work by Hyodo et al (1994), triaxial compression and extension tests were conducted on both normally consolidated undisturbed and reconstituted marine clays with a liquid limit of 124·2%, a plastic limit of 51·4% and a plasticity index of 72·8%. The monotonic axial load was applied at an axial strain rate of 0·1%/min.…”