Key factors affecting prediction of seismic pore water pressures in silty sands based on damage parameter

Energy-Based Pore Pressure Generation Models in Silty Sands under Earthquake Loading

“…Figure 11 shows the residual excess pore water pressure ratio versus cumulative dissipated energy for Ticino clean sand specimens prepared in the same initial state (a combination of packing density and initial vertical effective stress) but reconstituted using three different reconstitution methods, namely moist tamping, air pluviation, and water sedimentation. Interestingly, different soil fabrics induced by different reconstitution methods do not influence significantly the trend of Ru vs. W. A similar conclusion was made in previous research considering a pore-water-pressure-strain-based approach, while for stress-based PWP models this finding does not appear applicable [41]. Figure 11 shows the residual excess pore water pressure ratio versus cumulative dissipated energy for Ticino clean sand specimens prepared in the same initial state (a combination of packing density and initial vertical effective stress) but reconstituted using three different reconstitution methods, namely moist tamping, air pluviation, and water sedimentation.…”

“…Figure 11 shows the residual excess pore water pressure ratio versus cumulative dissipated energy for Ticino clean sand specimens prepared in the same initial state (a combination of packing density and initial vertical effective stress) but reconstituted using three different reconstitution methods, namely moist tamping, air pluviation, and water sedimentation. Interestingly, different soil fabrics induced by different reconstitution methods do not influence significantly the trend of R u vs. W. A similar conclusion was made in previous research considering a pore-water-pressure-strain-based approach, while for stress-based PWP models this finding does not appear applicable [41].…”

“…In this context, test results gathered from clean Ticino sand were analysed to verify the dependence of the correlation between R u and W for the initial fabric induced by the sand reconstitution method. Previous research did not thoroughly investigate this aspect, which needs further verification [35,41].…”

“…Conversely, strain-based models relate R u to the maximum cyclic shear strain γ max recorded in a specific applied uniform loading cycle. The proposed stress-or strain-based models have been calibrated using laboratory undrained cyclic triaxial [38][39][40], simple shear [3,25,41], and torsional tests [24,42]. In these tests, a sinusoidal shear stress or shear strain loading history is applied, and the increase in excess PWP with the number of loading cycles is measured.…”

Assessment of undrained cyclic resistance of sand with non-plastic fines under sustained shear stress using a critical state interpretation

“…The characterisation of these materials turns out to be problematic in engineering geology practice due to some peculiar features distinguishing the behaviour of these intermediate materials from that of the so called "text-book materials" (i.e. clean sands and pure clays) (Carraro and ratio e (Dash and Sitharam 2009;Porcino et al 2018aPorcino et al , 2021Gobbi et al 2022;Rahman and Sitharam 2020), relative density D R (Carraro et al 2003;Chien et al 2002;Gobbi et al 2022), skeleton void ratio e s (Carraro et al 2003;Dash and Sitharam 2009;Kuerbis et al 1988), and finally equivalent granular void ratio e* (Gobbi et al 2022;Porcino et al 2021;Rahman and Sitharam 2020;.…”