Computation of passive earth pressure coefficients for a vertical retaining wall with inclined cohesionless backfill

Abstract

Background: Understanding the behaviour of retaining walls subjected to earth pressures is an interesting but a complex phenomenon. Though a vast amount of literature is available in this study area, a majority of the literature, either theoretical or experimental, address the problem of a vertical retaining wall with a horizontal backfill. Therefore, it is decided to develop a limit equilibrium based protocol for the evaluation of passive earth pressure coefficients, K pγ for a vertical retaining wall resting against the inclined cohesionless backfill. Methods: The complete log spiral failure mechanism is considered in the proposed analysis. Though the limit equilibrium method is employed in the present investigation, an attempt is made to minimise the number of assumptions involved in the analysis. Results: The passive earth pressure coefficients are evaluated and presented for the different combinations of soil frictional angle ϕ, wall frictional angle δ and sloping backfill angle i. The solutions obtained from the proposed research work are very close to the best upper bound solutions given in the literature by Soubra and Macuh (P I CIVIL ENG-GEOTEC 155:119-131, 2002) for the K pγ coefficients. A comparison of the proposed K pγ values is also made with the other available theoretical as well as experimental results and presented herein. Conclusion: As the method developed herein is capable of yielding the best possible upper bound solution and being simple to implement, it could be considered as one of the alternatives for the evaluation of passive earth pressure coefficients for a vertical retaining wall resting against the inclined cohesionless backfill.

Discrete element analysis and analytical method on failure mechanism of retaining structures with narrow granular backfill

“…Equation ( 30) is a transcendental equation, which can be solved numerically with the dsolve function in MATLAB to obtain r b , θ b , r d , θ d , and h. The critical backfill width b 0 can be consequently obtained as follows: F I G U R E 1 4 Comparisons of active failure surface with different backfill widths between the proposed method and existing earth theories. 1,2,50 When the interface is fully smooth, combined with the geometry of the Mohr stress circle, the inclination between the failure surface and the horizontal plane at the intersection can be obtained. The critical backfill width b 1 can be presented as follows:…”

“…The proposed analytical method was adapted to investigate the impact of backfill widths and interface friction angles on the failure surfaces in the passive limit state and active limit state. Figure 13 50 are shown in Figure 13. It should be noting that there are serval existing studies about the earth pressure theories with a log-spiral failure surface.…”

Analysis of reinforced retaining wall failure based on reinforcement length

“…Based on the work of Yoo et al [19], reinforcements with a design strength 50 kN/m (EA) was applied in this study. Table 2 summarises the material parameters of the original ground, backfill, and retaining walls [3,10,15].…”

Field Measurements of Passive Earth Forces in Steep, Shallow, Landslide‐Prone Areas

“…The 3‐D limit equilibrium models included the calculation of the boundary earth forces through conventional formulations typically used in the design of retaining structures in the field of soil mechanics. Several methods are available in the geotechnical literature to estimate passive earth forces, such as limit equilibrium solutions (Janbu, ; Krey & Ehrenberg, ; Patki et al, ), plasticity theory (Chen & Rosenfarb, ), empirical equations (e.g., Brinch Hansen, ), the finite element model (Duncan & Mokwa, ), and the finite difference computer method (Benmebarek et al, ). The first pioneering studies developed by Coulomb () and Rankine () were performed beginning at the end of the eighteenth century and were based on similar assumptions: (1) soil is isotropic, homogeneous, and cohesionless; (2) rupture surfaces are a plane; (3) compressed wedges have a planar surface (i.e., the backfill inclination angle β is zero; see Figure for a schematic of the compressed wedge); (4) friction resistance is distributed uniformly along the rupture plane; (5) failure of the wedge is a rigid body undergoing translation; and (6) failure is a plane strain problem.…”