Fig. 4
From: Experiments on seepage-triggered cliff landslides using cohesive wet sand
Results of the \(h_{\mathrm{w}} = 2\) cm case (run 8, \(H = 20\) cm, \(h_{\mathrm{w}} / H = 0.10\)), in which no slide is triggered. a Images at \(t = 1320\) s, and b time-series data (5-point running averaged) of total stress \(\sigma\), pore water pressure u (left axis), and vertical displacement \(\Delta z\) (right axis). Back, front, and side indicate the sensor positions, and subscripts \(\mathrm {y}\) and \(\mathrm {z}\) indicate the normal direction (see Fig. 2b). A blue \(\bigtriangleup\) is the seepage time \(T_{\mathrm{seep}}\), which defines the onset of stage II. A star indicates the \(t = 1320\) s when the images shown in a were taken. The red vertical bar and blue \(\times\) (left axis) indicate the reference \(\sigma\) range, \(\sigma _0 \le \sigma \le {\tilde{\sigma }}_0\) [Eqs. (5), (6)], and the \(u = u_0\) [Eq. (7)], respectively