Determination of Active Earth Pressure on Rigid Retaining Wall Considering Arching Effect in Cohesive Backfill Soil

2016 ◽  
Vol 16 (3) ◽  
pp. 04015082 ◽  
Author(s):  
Pingping Rao ◽  
Qingsheng Chen ◽  
Yitao Zhou ◽  
Sanjay Nimbalkar ◽  
Gabriele Chiaro
2019 ◽  
Vol 4 (2) ◽  
pp. 15
Author(s):  
Nimbalkar ◽  
Pain ◽  
Ahmad ◽  
Chen

An accurate estimation of static and seismic earth pressures is extremely important in geotechnical design. The conventional Coulomb’s approach and Mononobe-Okabe’s approach have been widely used in engineering practice. However, the latter approach provides the linear distribution of seismic earth pressure behind a retaining wall in an approximate way. Therefore, the pseudo-dynamic method can be used to compute the distribution of seismic active earth pressure in a more realistic manner. The effect of wall and soil inertia must be considered for the design of a retaining wall under seismic conditions. The method proposed considers the propagation of shear and primary waves through the backfill soil and the retaining wall due to seismic excitation. The crude estimate of finding the approximate seismic acceleration makes the pseudo-static approach often unreliable to adopt in the stability assessment of retaining walls. The predictions of the active earth pressure using Coulomb theory are not consistent with the laboratory results to the development of arching in the backfill soil. A new method is proposed to compute the active earth pressure acting on the backface of a rigid retaining wall undergoing horizontal translation. The predictions of the proposed method are verified against results of laboratory tests as well as the results from other methods proposed in the past.


2021 ◽  
Author(s):  
Jun-feng Jiang ◽  
Qi-hua Zhao ◽  
Shuairun Zhu ◽  
Sheqin Peng ◽  
Yonghong Wu

Abstract A new approach is proposed to evaluate the non-limit active earth pressure in cohesive-frictional based on the horizontal slices method and limit equilibrium method. This approach takes into account the arching effect, displacement, average shear stress of the soil slice, rupture angle and tension cracks. The accuracy of the proposed method is demonstrated by comparing the experimental results and other theoretical methods. The comparison results show that the proposed approach is suitable for calculating the non-limit active earth pressure in cohesive-frictional soil and cohesionless soil. Additionally, the empirical formulations of the mobilized internal friction angle and soil-wall interface friction angle usually used to cohesionless soil are still applied to cohesive-frictional soil through comparison calculated results of other theoretical methods and finite element method. Some valid formulations of the rupture angle and tension cracks were derived considering the cohesion, wall height, and unit weight.


2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Sahar Ghobadi ◽  
Hadi Shahir

Purpose The purpose of this paper is to study the distribution of active earth pressure in retaining walls with narrow cohesion less backfill considering arching effects. Design/methodology/approach To this end, the approach of principal stresses rotation was used to consider the arching effects. Findings According to the presented formulation, the active soil pressure distribution is nonlinear with zero value at the wall base. The proposed formulation implies that by increasing the frictional forces at both sides of the backfill, the arching effect is increased and so, the lateral earth pressure on the retaining wall is decreased. Also, by narrowing the backfill space, the lateral earth pressure is extremely decreased. Originality/value A comprehensive analytical solution for the active earth pressure of narrow backfills is presented, such that the effects of the surcharge and the characteristics of the stable back surface are considered. The magnitude and height of the application of lateral active force are also derived.


2020 ◽  
Vol 10 (9) ◽  
pp. 3243
Author(s):  
Meilin Liu ◽  
Xiangsheng Chen ◽  
Zhenzhong Hu ◽  
Shuya Liu

For c-φ soil formation (cohesive soil) of limited width with ground surface overload behind a deep retaining structure, a modified active earth pressure calculation model is established in this study. And three key issues are addressed through improved soil arching effect. First, the soil-wall interaction mechanism is determined by considering the soil arching effect. The slip surface of a limited soil is proved to be a double-fold line passing through the retaining wall toe and intersecting the side wall of the existing underground structure until it reaches the ground surface along the existing side wall. Second, the limited width boundary is explicated. And third, the variation in the active earth pressure from parameters of limited c-φ soil is determined. The lateral active earth pressure coefficient is nonlinear distributed based on the improved soil arching effect of the symmetric catenary curve. Furthermore, the active earth pressure distribution, the tension crack at the top of the retaining wall and the resultant force and its action point were obtained. By comparing with the existing analytical methods, such as the Rankine method, it demonstrates that the model proposed in this study is much closer to the measured and numerical results. Ignoring the influence of soil cohesion and the limited width will exponentially reduce the overall stability of the retaining structure and increase the risk of accidents.


2015 ◽  
Vol 1089 ◽  
pp. 286-291
Author(s):  
Chao Tian ◽  
Yong Gang Li ◽  
Zhi Xiong Zhang

For the retaining wall in translation, in this paper the writers present the minor principal stresses trajectory which named minor principal stress arches. By discussing the results of the various arch curves in arching effect with different displacements of retaining wall which include the arch curves in ultimate model of soil and the arch curves in none limit state of soil. It gets the soil arch curve change rule under different state of the displacements, different friction angles and different height: the arch curve turn gentle when the displacements increase.


2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Li Liu ◽  
Zhen Yang ◽  
Pan Zhou ◽  
Hongwei Yang

The traditional Coulomb’s earth pressure theory does not consider the effect of local surcharge on the lateral earth pressure and its critical failure angle. However, in practice, local surcharges commonly act on the surface of frozen backfill that is affected by freeze-thaw actions in cold regions and tend to affect the active thrust and its position. In paper, analytical solutions for estimating the active thrust, critical wedge failure angle, and action position subject to a local surcharge in cold regions are proposed. Herein, the simplified equivalent moment of surcharge is adopted on the premise of maintaining Coulomb’s earth pressure assumptions. The formula derivation is provided as a typical example to obtain the active thrust, critical wedge failure angle, and its position under a strip surcharge. Compared with previous approaches, the proposed solutions lead to easier evaluation of all indexes associated with Coulomb’s active earth pressure. Meanwhile, the expressions of Coulomb’s earth pressure under other types of nonuniform loading acting on the wall are discussed. In addition, sensitivity is performed to assess the effect of some main parameters. The results indicate that the dip angle of retaining wall-back and the friction angle of frozen backfill soil are two most significant indexes that influence the active thrust and its position.


2020 ◽  
Vol 2020 ◽  
pp. 1-11
Author(s):  
Weidong Hu ◽  
Kangxing Liu ◽  
Xinnian Zhu ◽  
Xiaolong Tong ◽  
Xiyu Zhou

The horizontal differential layer element method was used to study the active earth pressure of the finite-width soil formed by the rigid retaining wall for the embankment or adjacent foundation pits. The cohesionless soil was taken as the research object, and the soil arch theory was introduced based on the translation mode of rigid retaining wall and the linear sliding fracture surface. The minor principal stress line was assumed as circular, considering the deflected principal stress as soil arching effect. The shear stress between level soil layers in the failure wedge was calculated, and the differential level layer method was modified. Then, the theoretical formula of the active earth pressure, the resultant earth pressure, and the point of application of resultant earth pressure were obtained using this revised method. The predictions by the proposed formula were compared with the existing methods combined with the cases. It is shown that the resultant finite pressure increases gradually and approaches to Coulomb active earth pressure values when the soil is infinite, with the increase of the ratios of the backfill width to height. Moreover, the horizontal pressure for limited soils is distributed nonlinearly along the wall height. Considering the shear stress between level soil layers and the soil arching effect, the position of application point of the resultant active earth pressure by the proposed formulation is higher than that of Coulomb’s solution. The wall is rougher, and the resultant pressure will be smaller. The application point distance from the bottom of the wall will increase. Finally, an experiment was conducted to verify the distribution of the active earth pressure for finite soil against rigid retaining wall, and the research results agree well with those of the experimented observations.


2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Zheng-zhen Wang ◽  
Rang-cheng Kou ◽  
Yong Zhou ◽  
Tian-zhong Ma

At present, most seismic earth pressure theories have the limitations of complex derivation process and difficult solution. To solve these problems, considering the deflection of small principal stress caused by soil arching effect, the central arc soil arch was approximated to two inclined linear soil arches, which can greatly simplify the derivation process. Firstly, by improving the combination of differential thin-layer element method and pseudostatic method, the theoretical formulas of seismic active earth pressure intensity, resultant force size, and resultant force action point under translation mode (T mode) were derived and were verified by experimental results. Then, the influence of soil internal friction angle, wall-soil friction angle, and seismic coefficient on seismic active earth pressure theory was analyzed. The results show that the seismic active earth pressure is nonlinearly distributed, and the seismic horizontal coefficient has a greater influence than other influence factors. The theoretical results can provide reference for the seismic design of retaining wall.


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