Study on Moisture Migration Law of Unsaturated Loess Slope Under Seismic Effect

Rainfall infiltration is one of the main factors inducing instability of loess slopes. Based on existing experiments and similarity theory, a loess slope model was established. Pore water pressure sensors were buried at different positions on the slope, and sine wave scanning was used. Large shaking table tests were conducted to measure the acceleration under eight different working conditions. The experimental results indicate that the pore pressure at point PD4 gradually decreases; When loaded to 400 gal, its pore pressure tends to converge; When the acceleration reaches 600 gal, it is basically close to 0. At 100 gal, the changes in pore pressure at different locations of the loess slope measurement points are basically the same, except for a few significant increases. When loaded to 600 gal, the change in pore pressure at point pC4 is most significant, with pC4 > pB4 > pA4 > pD4 ≥ 0. It has been revealed that under different seismic effects, the location of the site affects the changes in pore pressure, and there is a significant difference in the rate of water seepage. This slope location is also the most prone to failure.