Static and cyclic liquefaction potential of Fraser Delta sand in simple shear and triaxial tests

Abstract

The potential for static and cyclic liquefaction of the sand that underlies the highly seismic Fraser Delta is assessed under simple shear test conditions, typical of an earthquake shaking. A comparison of liquefaction potential is also made between simple shear and conventional triaxial stress conditions. It is shown that the liquefaction potential of sand is profoundly influenced by the stress path. The reduction factors currently applied to the cyclic triaxial resistance for representing simple shear response may involve a large degree of conservatism in design. A direct measurement of soil behaviour under stress conditions typical of earthquake loading may thus have large economic benefits. Key words: sand, liquefaction, static, cyclic, triaxial, simple shear.

Microstructure evolution of granular soils in cyclic mobility and post-liquefaction process

“…From Fig. 14b, we can also observe that a packing with higher density needs more cycles to liquefy, which is consistent with laboratory tests (e.g., [29]). It is also worth pointing out that although it is not reported in details in this paper, a similar decreasing trend of D c,min can also be observed using elongated particles, implying that the trend is not affected by the particle shape.…”

2nd Ishihara Lecture: SPT- and CPT-based relationships for the residual shear strength of liquefied soils

“…6 for Fraser river sand by Vaid and Sivathayalan [30]. The bullet symbols on this figure identify points of minimum shear resistance which correspond to the transition from an incrementally contractive to an incrementally dilative response in undrained shearing (i.e., phase transformation) and which have also been called a quasi-steady state condition [12].…”

“…Undrained direct simple shear tests on Fraser river sand at a range of relative densities by Vaid and Sivathayalan[30].…”

“…Undrained shear resistance ratios mobilized in direct simple shear tests on Fraser river sand at different relative densities and shear strain levels (after Vaid and Sivathayalan[30] and Vaid et al[31]). …”

Effect of Particle Morphology on the Monotonic Response of Gravel-Sized Soils through Large-Scale Simple Shear Testing

“…Vaid and Sivathayalan (1996) state that understanding the static response of a material is crucial in the assessment of the potential for flow slides and earthquake-induced displacements. However, there are inherent difficulties in testing gravel in the laboratory due to specimen size restrictions.…”