scholarly journals Influence of Lightweight Foamed Concrete as Backfill Material on Stress and Deformation of Buttressed Earth-Retaining Wall

Geofluids ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Youqiang Qiu ◽  
Yang Liu ◽  
Liujun Zhang ◽  
Zhanqi Wang
Keyword(s):  
Retaining Wall ◽  
Soft Soil ◽  
Earth Pressure ◽  
Scale Model ◽  
Range Analysis ◽  
Distribution Form ◽  
Orthogonal Experiments ◽  
Earth Pressures ◽  
Foamed Concrete ◽  
Stress And Deformation

Controlling settlement and earth pressure behind retaining wall in soft soil area are ongoing practical problems for the construction and operation of highway, which are mainly caused by the poor nature of soft soil. To reduce the pushing force on retaining wall and subgrade settlement, the authors propose the use of lightweight foamed concrete as subgrade filler behind the buttressed earth-retaining wall. However, the mechanical properties and deformation behavior of the buttressed earth-retaining wall remain unknown when lightweight foamed concrete is used as a backfill behind the wall. To solve this problem, a scale model of the subgrade filled with lightweight foamed concrete behind the buttressed earth-retaining wall is established to determine its stress and deformation characteristics under different factors. Lateral earth pressures and wall displacements at different elevations of the retaining wall model were monitored during the tests. Then, a series of orthogonal experiments are conducted to analyse and compare the effects of overload, density, and replacement thickness of lightweight foamed concrete on the earth pressure and displacement of this retaining wall. The results show that the size of earth pressures at the same position of retaining wall is affected by overload, density, and replacement thickness of lightweight foamed concrete, but its change of distribution form is only related to the replacement thickness of this backfill. Additionally, the primary-secondary relations of different factors’ influence extent on the forces and deformation of the buttressed earth-retaining wall filled with lightweight foamed concrete as backfill are obtained by using range analysis method.

Estimation of Active Earth Pressure on Retaining Wall with Translation Mode

2013 ◽  
Vol 639-640 ◽  
pp. 682-687
Author(s):  
Qing Guang Yang ◽  
Jie Liu ◽  
Jie He ◽  
Shan Huang Luo
Keyword(s):  
Retaining Wall ◽  
Earth Pressure ◽  
Friction Angle ◽  
Active Earth Pressure ◽  
Action Point ◽  
Layer Analysis ◽  
Earth Pressures ◽  
Reduction Coefficient ◽  
Point Of Intersection ◽  
Theoretical Results

Considering the movement effect of translation mode，friction angle reduction coefficient and method of bevel-layer analysis,estimation of active earth pressures is deduced for cohesiveless soil retaining wall with translation mode.In order to validate the feasibility of the proposed approach，a model test for active earth pressures was conducted in laboratory;and the proposed method was used to analyze this model. Experimental and theoretical results indicate that the curve of active earth pressure increases firstly and decreases then along the depth of retaining wall with different values of s/sc,and it has a point of intersection with the curve of Coulomb active earth pressure at the depth of 0.6H，where H is the wall height. Further study indicates that the action point position of the active earth pressure is higher than 1/3 times wall height.

Analysis of Passive Earth Pressure and Displacements of Retaining Walls Using Pseudo-Dynamic Approach

2010 ◽  
Vol 1 (1) ◽  
pp. 88-109
Author(s):  
B. Munwar Basha ◽  
G. L. Sivakumar
Keyword(s):  
Dynamic Method ◽  
Retaining Wall ◽  
Earth Pressure ◽  
Passive Earth Pressure ◽  
Planar Mechanisms ◽  
Composite Failure ◽  
Earth Pressures ◽  
Planar Failure ◽  
Seismic Accelerations ◽  
The Comparative Study

Using additional dynamic parameters in the pseudo-static method like shear wave and primary wave velocities of soil, phase change in the shear and primary waves, and soil amplification for seismic accelerations, one can benefit from another useful tool called pseudo-dynamic method to solve the problem of earth pressures. In this study, the pseudo-dynamic method is used to compute the seismic passive earth pressures on a rigid gravity retaining wall by considering both the planar failure and composite failure (log-spiral and planar) mechanisms. To validate the present formulation, passive earth pressure computed by the present method are compared with those given by other authors. Seismic passive earth pressure coefficients are provided in tabular form for different parameters. The sliding and rotational displacements are also computed and results of the comparative study showed that the assumption of planar failure mechanism for rough soil-wall interfaces significantly overestimates passive earth pressure and underestimate the sliding and rotational displacements.

Earth Pressure Analysis and Retaining Walls

2015 ◽  
pp. 313-410
Keyword(s):  
Retaining Wall ◽  
Earth Pressure ◽  
Retaining Walls ◽  
Wall Friction ◽  
Underground Structures ◽  
Retaining Structure ◽  
Earth Pressures ◽  
Braced Excavations ◽  
Surcharge Load ◽  
Line Loads

Retaining walls are structures used not only to retain earth but also water and other materials such as coal, ore, etc. where conditions do not permit the mass to assume its natural slope. In this chapter, after considering the types of retaining wall, earth pressure theories are developed in estimating the lateral pressure exerted by the soil on a retaining structure for at-rest, active, and passive cases. The effect of sloping backfill, wall friction, surcharge load, point loads, line loads, and strip loads are analyzed. Karl Culmann's graphical method can be used for determining both active and passive earth pressures. The analysis of braced excavations, sheet piles, and anchored sheet pile walls are considered and practical considerations in the design of retaining walls are treated. They include saturated backfill, wall friction, stability both external and internal, bearing capacity, and proportioning the dimensions of the retaining wall. Finally, a brief treatment of earth pressure on underground structures is included.

scholarly journals Experimental and Numerical Investigation on the Effects of Foundation Pit Excavation on Adjacent Tunnels in Soft Soil

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Zi-Tian Yu ◽  
Heng-Yu Wang ◽  
Wenjun Wang ◽  
Dao-Sheng Ling ◽  
Xue-Dong Zhang ◽  
...  
Keyword(s):  
Retaining Wall ◽  
Soft Soil ◽  
Shear Bands ◽  
Earth Pressure ◽  
Bending Moment ◽  
Surface Settlement ◽  
Diaphragm Wall ◽  
Foundation Pit ◽  
Obvious Effect ◽  
Diaphragm Walls

Excavations near an existing tunnel are often encountered in underground construction. The influence of the excavation on the adjacent tunnels is not yet fully understood. This study presented a centrifugal model test about excavation next to existing tunnels in soft soil foundation. The bending moment of diaphragm wall, surface settlement, tunnel deformation, and earth pressure around the tunnel were mainly studied. The influence of tunnel location is further studied by numerical simulation. During the stabilization stage of foundation pit, the diaphragm walls present convex deformation towards foundation pit, and the surface settlement outside the diaphragm wall appears to be the concave groove type. During the overexcavation stage, the diaphragm walls are almost damaged, and the shear bands are nearly tangent to the tunnels. The displacement of the tunnels and the surface settlement rapidly increase. The deformation of the diaphragm wall and the surface settlement are limited by the existing tunnel. The numerical results indicate that the change of tunnel location has little effect on the retaining wall but an obvious effect on the tunnel itself.

Analysis of active earth pressure against rigid caissons backfilled with crushed rock and sand

2009 ◽  
Vol 46 (10) ◽  
pp. 1216-1228 ◽  
Author(s):  
Kyuho Paik ◽  
Myung Sagong ◽  
Hyungjoo Lee
Keyword(s):  
Retaining Wall ◽  
Slope Angle ◽  
Earth Pressure ◽  
Crushed Rock ◽  
Active Earth Pressure ◽  
Active Force ◽  
Marine Structures ◽  
Earth Pressures ◽  
Backfill Materials ◽  
New Formulation

Arching effects in backfill materials generate a nonlinear active earth-pressure distribution behind a rough, rigid retaining wall. There are several analyses for estimating the nonlinear active earth pressures on a retaining wall exerted by a homogeneous backfill in the presence of arching. However, it is not possible to use these analyses for a caisson backfilled with crushed rock and sand, which is common in marine structures. In this study, a new formulation is proposed for calculating the nonlinear active earth pressure acting on a caisson backfilled with crushed rock and sand. The new formulation allows important insights, including the dependence of the slope angle of the crushed rock – sand interface that minimizes the active force and overturning moment on the caisson on the shear strengths of the crushed rock and sand and the geometry of the problem.

scholarly journals Seismic Earth Pressures of Retaining Wall from Large Shaking Table Tests

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Changwei Yang ◽  
Jian Jing Zhang ◽  
Qu Honglue ◽  
Bi Junwei ◽  
Liu Feicheng
Keyword(s):  
Wenchuan Earthquake ◽  
Retaining Wall ◽  
Time History ◽  
Earth Pressure ◽  
Shaking Table ◽  
Rock Foundation ◽  
Shaking Table Tests ◽  
The Wenchuan Earthquake ◽  
Earth Pressures ◽  
Soil Foundation

To ascertain seismic response of retaining wall in the Wenchuan earthquake, large shaking table tests are performed and an acceleration record is acted in 3 directions. In the tests, acceleration time history recorded at Wolong station in the Wenchuan earthquake is used to excite the model wall. Results from the tests show that the location of dynamic resultant earth pressure is 0.35–0.49 H from toe of the wall for road shoulder retaining wall on rock foundation, 0.33–0.42 H for embankment retaining wall on rock foundation, and 0.46–0.77 H for road shoulder retaining wall on soil foundation. Besides, dynamic earth pressure increases with the increase of ground shaking from 0.1 g to 0.9 g and the relationship is nonlinear. The distribution is closed to for PGA less than 0.4 g but larger for PGA larger than and equal to 0.4 g, especially on the soil foundation. After the comparison of measured earth pressures and theoretical results by pseudodynamic method and pseudostatic method, results of the former are consistent with those of the shaking table test, but results of the latter method are smaller than measured.

Analyses of Earth Pressure on Gridding Concrete Retaining Wall in the Excavation of Deep Foundation Pit in Soft Soil Area

2011 ◽  
Vol 52-54 ◽  
pp. 2181-2186
Author(s):  
Guang Zhu Zhou ◽  
Xu Wei ◽  
Chen Yu
Keyword(s):  
Retaining Wall ◽  
Soft Soil ◽  
Earth Pressure ◽  
Front Wall ◽  
Three Dimension ◽  
Deep Foundation ◽  
Foundation Pit ◽  
Finite Element Software ◽  
The Earth ◽  
Practical Engineering

This paper is mainly to study earth pressure on Gcrw used as a new kind of supporting structures in the excavation of deep foundation pits in soft soil region. On the basis of the simulation of step by step excavation by using big finite element software Abaqus/CAE and considering three-dimension elastoplastic stress state, the characteristics of different earth pressure are systematically discussed upon practical engineering. By comparing simulation results with calculated results based on calculation formula of Rankine Theory, it can be seen that the earth pressure in active zone is different from theoretic active earth pressure and earth pressure at rest while walls and soil in the gridding are regarded as a whole, which is greater than the former and somewhere similar to the latter, the earth pressure in passive zone is bigger than theoretic value of passive earth pressure, it is the tensive force from partition wall that prevent the front wall from overturning. These conclusions will be helpful for design and construction of new retaining wall.

scholarly journals Impact of wall movements on the location of passive Earth thrust

2021 ◽  
Vol 13 (1) ◽  
pp. 570-581
Author(s):  
Meriem F. Bouali ◽  
Mahdi O. Karkush ◽  
Mounir Bouassida
Keyword(s):  
Retaining Wall ◽  
Earth Pressure ◽  
Friction Angle ◽  
Retaining Walls ◽  
General Assumption ◽  
Wall Friction ◽  
Wall Movement ◽  
Numerical Predictions ◽  
Test Models ◽  
Earth Pressures

Abstract The general assumption of linear variation of earth pressures with depth on retaining structures is still controversial; investigations are yet required to determine those distributions of the passive earth pressure (PEP) accurately and deduce the corresponding centroid location. In particular, for rigid retaining walls, the calculation of PEP is strongly dependent on the type of wall movement. This paper presents a numerical analysis for studying the influence of wall movement on the PEP distribution on a rigid retaining wall and the passive earth thrust location. The numerical predictions are remarkably similar to existing experimental works as recorded on scaled test models and full-scale retaining walls. It is observed that the PEP varies linearly with depth for the horizontal translation, but it is nonlinear when the movement is rotational about the top of the retaining wall. When rotation is around the top of the wall, the resultant of PEP is located at a depth that varies between 0.164 and 0.259H of the wall height measured from the base of the wall, which is lesser than 1/3 of the wall height. The passive earth thrust location is highly affected by the soil–wall friction angle, especially when the friction angle of the backfill material increases. Despite the herein presented results, further experiments are recommended to assess the corresponding numerical predictions.

Evaluation of Earth Pressures Against Rigid Retaining Structures with RTT Mode

2010 ◽  
Vol 168-170 ◽  
pp. 200-205
Author(s):  
Fei Song ◽  
Jian Min Zhang ◽  
Lu Yu Zhang
Keyword(s):  
Pressure Distribution ◽  
Formation Mechanism ◽  
Retaining Wall ◽  
Experimental Studies ◽  
Earth Pressure ◽  
Retaining Walls ◽  
Wall Displacement ◽  
The Earth ◽  
Earth Pressures ◽  
Mode A

The evaluation of earth pressure is of vital importance for the design of various retaining walls and infrastructures. Experimental studies show that earth pressures are closely related to the mode and amount of wall displacement. In this paper, based on the reveal of the formation mechanism of earth pressures against rigid retaining wall with RTT mode, a new method is proposed to calculate the earth pressure distribution in such conditions. Finally, the effectiveness of the method is confirmed by the experimental results.

Numerical simulation of an instrumented cantilever retaining wall

2011 ◽  
Vol 48 (9) ◽  
pp. 1303-1313 ◽  
Author(s):  
Ashok K. Chugh ◽  
Joseph F. Labuz
Keyword(s):  
Numerical Simulation ◽  
Field Data ◽  
Retaining Wall ◽  
Earth Pressure ◽  
Satisfactory Explanation ◽  
Foundation Soil ◽  
Pressure Coefficients ◽  
Working Hypothesis ◽  
Earth Pressures ◽  
Practical Implications

The field data of an instrumented cantilever retaining wall are reexamined to develop a working hypothesis for the mechanism that explains the observed response. The field data are in terms of earth pressures and wall movements (deflection, translation, and rotation) from the start to completion of backfilling. The observed response demonstrates strong interaction between the retaining wall and foundation soil. Traditional calculations based on earth pressure coefficients had not provided a satisfactory explanation for the measured responses during placement of backfill. In this paper, the working hypothesis, and results from its implementation in a continuum-mechanics-based computer program are presented. The numerical model results, displacements and earth pressures, are in general agreement with the field data for all stages of backfill placement and provide a clear exposition to the observed response. Practical implications of the work are included.

Sign in / Sign up

Export Citation Format

Share Document