The liquefaction of saturated sand-gravel material samples from the Xinjiang valley were investigated under cyclic loading. A series of large-scale dynamic triaxial tests were used to determine the dynamic characteristics of the sand-gravel sample under different confining pressures, consolidation stress ratios, and stress levels. A suitable pore water pressure growth model is proposed for the sand-gravel and sand materials. The number of cycles required to cause liquefaction was an important parameter in the dynamic pore water pressure growth model. A method to determine the number of cycles was proposed and verified by a large number of experimental data. The presentation of the pore water pressure simulation results demonstrates that the proposed pore water pressure growth model accurately characterizes the dynamic pore water pressure development in sand-gravel under cyclic loading and is also applicable to sand. The proposed pore water pressure growth model can be used to study the anti-liquefaction characteristics of foundation and dam materials of high earth-rock dams and high sand-gravel dams on deep overburdens.

South Korea has implemented borehole -type seismometers for reliable earthquake observations and earthquake early -warning systems, with approximately 85% of seismometers being replaced by borehole -type seismometers after the Gyeongju earthquake. Although these seismometers are more effective at detecting earthquakes owing to the reduced artificial ambient noise, they do not record surface -level shaking. Therefore, it is necessary to estimate ground surface shaking directly associated with potential damage when using borehole -type seismometers without surface sensors. This study investigated and compared various methods, including the stochastic point -source ground -motion model, transfer function based on ambient noise, and one-dimensional site response, to estimate horizontal seismograms of the ground surface. We assessed the accuracy of these methods by comparing the waveforms generated in event cases (magnitude from 2.5 to 5.8, with epicentral distances spanning 22 km - 209 km) in terms of Fourier spectra, intensity, and spectral acceleration. Among the methods assessed, the transfer function approach, which does not account for the geophysical characteristics such as V S 30 , proved to be the most appropriate for correcting ground -surface effects.