Influences of Pore‐Water Pressure on Slope Stability considering Strength Nonlinearity

Abstract

The pore-water pressure is a vital factor in determining the slope stability. To deal with the stability of slopes undergoing pore-water pressures, this paper used the pore-water pressure coefficient to develop the three-dimensional limit analysis method for slope stability evaluation with a nonlinear strength envelope. For numerical slope examples, the critical heights and corresponding critical slip surfaces associated with linear and nonlinear envelopes were derived by using a numerical optimization procedure. The influences of pore-water pressures on the slope stability were addressed by comparing the upper-bound solutions derived by linear and nonlinear strength envelopes (the linear and nonlinear results for short). The obtained two critical inclinations between the linear and nonlinear results both decrease and gradually approach with increasing pore-water pressure coefficient. For most slopes subjected to pore-water pressures, using the linear Mohr–Coulomb envelope will obviously overestimate the slope critical height. The overestimation resulted from the linear criterion will become more distinct for slopes with smaller widths. Besides, the presented results showed that the equivalent internal friction angle tends to have a weaker increasing trend for steeper slopes as pore-water pressure coefficient increases. Hence, when pore-water pressure coefficient increases, the critical slip surfaces of gentle slopes with nonlinear strength criteria become shallower, but the critical slip surfaces of steep slopes seem to have no consistent change law. These results and analyses can illustrate the significance of the application of nonlinear strength envelopes in slope stability evaluation considering pore-water pressures and provide certain reference advice in slope engineering design and landslide prevention.

Stability Assessment of the Slopes of an Oceanside Coral Limestone Quarry under Drawdown Condition of Semidiurnal Ocean Tides

“…Other researchers investigating pore pressure variations in rock slopes, such as Saada et al [33] and Preisig et al [34], also made similar observations. The variations in shear strain patterns depicting the critical slip surfaces are also corroborated by results reported in the analysis by Wu et al [35].…”

Study on the mechanism of water-induced degradation of slip zone soils and FDEM coupled simulation of slopes based on multi-scale characteristic

“…Currently, many studies have been conducted on the effects of rainfall on slope stability. including indoor physical experiments, dynamic monitoring of the relationship between rainfall and landslide deformation, simulation analysis of rainfall-induced landslides [6,7]. Montgomery [8] and Jakob [9] proposed a more reasonable rainfall threshold based on the hydraulics and landslide stability model, considering rainfall and pore water pressure, permeability, matrix suction, landslide morphology, and bedrock structure.…”

Reconstruction of Natural Slope Stability by Limit Equilibrium Methods and Finite Element Methods

“…The results of low shear strength values in each slice of the limit equilibrium analysis for saturated conditions also indicate that the slope is in an unsafe condition which is supported by the development of shear and tensile strains in the finite element method analysis in the slope slide plane area which causes the stress distribution in the actual landslide area to be unstable. permeability in the soil cause infiltration on the slope and additional load, namely pore water, so that the shear strength of the slope will decrease and disrupt stability (Mukhlisin and Naam, 2015;De Leon and Garduño, 2020;Wu et al, 2021). The shear strength parameters, cohesion (C) and internal friction angle (ϕ) influence the shear strength of the slope material, especially changes in cohesion (Harabinová and Panulinová, 2020).…”