In the case of saturated deposits, pore pressure distribution depends on the variations of hydraulic conductivity, on the hydraulic boundary conditions and—under transient conditions—on the coefficient of volume change (i.e. of water on cut and fill slope stability is briefly discussed below. In order to estimate the factor of safety F s for a slope in terms of effective stress (i.e. SLOPE/W can effectively analyze both simple and complex problems for a variety of slip surface shapes, pore-water pressure conditions, soil properties, and loading conditions.

Effects of Water on Slope Stability 6. This paper presents a multi-disciplinary approach for the determination of these two factors and for the construction of a reliable model of the subsoil for the slope stability analysis. Types of soil; Time during which the excavation is required to be open; Allowable degree of risk of slipping which is determined based on the existing structures and new constructed buildings around the excavation area.

Alternatively, shear strength may be decreased by weathering, changes in pore water pressure, and organic material. The effect of re-tarded pore water pressure release on slope stability is primarily dependent on the permeability of the soil, the compressibility of the pore water, i.e. Slope stability analysis SLOPE/W is the leading slope stability software for soil and rock slopes. ... exceeded, as the excess pore water pressure dissipates consolidation occurs, and the ... A slope that extends for a relatively long distance and has a consistent subsurface profile may u Pore water pressure U Normal force exerted by pore water pressure on base of slice W Weight of an element x Horizontal distance to edge of slice in Janbu analysis (from toe) y Janbu: Height of slip surface (positive down from datum) y Infinite slope: Distance (“depth”) measured normal to slope y. t The Effects of pore water pressure have been studied by Michalowski (1995) and Kim et al (1999) in 2D slope stability problems based on limit analysis method.

(deterministic) approach to slope stability analysis and design, the shear strength, slope geometry, external loads, and pore water pressures are assigned specific unvarying values. SLOPE/W is commonly used to assess stability of roadways, rail beds, bridge abutments, and MSE walls both during and after construction. Water pressure weakens the ties between the particles and they tend to slip, a fact that reduces the stability of the slope. Slope stability is influenced by many factors, among which are subsoil structure and pore water pressure distribution. Pore water pressures in Equation 2 are due to the free pore water existing between soil particles. As you all know in drained condition, the pore water can easily drain out from the soil matrix while in undrained condition the pore water is unable to drain out or the rate of loading is much quicker than the rate at which the pore water is able to drain out. 7. Slope stability design should be consistent with state-of-the-practice design guidelines, including but not limited to the referenced publications in Section 7.7. GEO-SLOPE International Ltd, Calgary, Alberta, Canada www.geo-slope.com SEEP/W Example File: Seepage and stability.doc (pdf) (gsz) Page 1 of 6 SEEP/W generated pore-water pressures in SLOPE/W stability analysis 1 Introduction The objective of this illustration is to observe how to use finite element pore-water pressure results in a CHAPTER 10 Slope Stability Analysis NYSDOT Geotechnical Page 10-8 January 21, 2014 Design Manual 10.2.4 Pore Water Pressure A change in effective stress caused by pore water pressure is a major contributor of slope failures because the pressures tend to alter the shear strength of the soil along the shear zone. Abstract. SLOPE/W can analyze stability at each construction stage, including the effects of pore-water pressure changes and interaction with reinforcement. Water drainage: The presence of water in the soil or the rock mass causes increased pore water pressure. 1 Introduction. Slope stability design shall be evaluated using conventional limit equilibrium methods, and analyses should be performed using a state-of-the-practice The field of slope stability encompasses static and dynamic stability of slopes of earth and rock-fill dams, slopes of other types of embankments, excavated … Porous materials like soils have different design properties under drained and undrained conditions. in the long-term condition), the pore water pressure must be known. Shear strength may be decreased by weathering, changes in pore water pressure, and organic material. Hence, total pore-water pressures immediately after excavation are lower than the ultimate equilibrium values, leading to a reduction of the average effective stresses in the slope and subsequently threatening stability in the long term. Drains are used to reduce water …

The value of the calculated factor of safety depends on the judgments made in selecting the A slope previously stable may … Performing Organization Report No. Appendix D discusses shear strength value selection. Factors Affecting Slope Stability in Open Excavation. Author(s) Tommy C. Hopkins, David L. Allen, Robert C. Deen 435 -9. Slope stability is calculated by balancing the shear stress and strength of the soil in various possible conditions. This is frequently the greatest source of inaccuracy in slope stability work, since the determination of the most critical conditions of pore water pressure is complex and costly.