Soil Arching in a Piled Embankment under Dynamic Load

2015 ◽  
Vol 15 (6) ◽  
pp. 04014094 ◽  
Author(s):  
Gao-xiao Han ◽  
Quan-mei Gong ◽  
Shun-hua Zhou
Keyword(s):  
Dynamic Load ◽  
Soil Arching ◽  
Piled Embankment

Analysis of Soil Arch under Dynamic Load

2012 ◽  
Vol 193-194 ◽  
pp. 939-948
Author(s):  
Mei Fang Li ◽  
Quan Mei Gong ◽  
Shun Hua Zhou
Keyword(s):  
Dynamic Load ◽  
Load Transfer ◽  
The Finite Element Method ◽  
Negative Effects ◽  
Soil Arching ◽  
Transfer Path ◽  
Numerical Studies ◽  
Calculation Results ◽  
Total Settlement ◽  
Soil Arch

Aroused by the differential stiffness of pile and soil, the upper load on subgrade is apt to be transferred to pile rather than soil among piles in pile supported embankment(soil arching effect), which optimizes the load-transfer path and effectively limits total settlement of the subgrade. In this paper the properties of soil arch under dynamic load have been investigated by performing numerical studies using the Finite Element Method. The influence of stiffness difference between soil and pile on the soil arch is also proposed in this paper. According to the calculation results, the softer the soil between piles is, the larger proportion of load imposes on pile. Dynamic load has negative effects on the static soil arch, but it does not ruin the shape of the arch. Simultaneously, the larger N (the ratio of dynamic modulus of pile to that of soil)is, the weaker the negative effects of dynamic load on static soil arch are. The static soil arch (soil arch formed when the model only bears static load) has optimized the load transformation path, leading more load undertaken by the pile. Besides, When the stiffness difference between pile and soil among piles is relatively small, the height of soil arch increases sharply with the decrease of N; while when the stiffness difference reaches some certain value, the further increasing of N has little influence on soil arch’s height.

scholarly journals Analytical methods for stress transfer efficacy in the piled embankment

2020 ◽  
Vol 61 (HTCS6) ◽  
pp. 81-87
Author(s):  
Hung Van Pham ◽  
Phuc Dinh Hoang ◽  
Thinh Duc Ta ◽  
Keyword(s):  
Analytical Methods ◽  
Load Transfer ◽  
Soft Soil ◽  
Stress Transfer ◽  
Soil Improvement ◽  
Soil Arching ◽  
Negative Skin Friction ◽  
Load Transfer Mechanism ◽  
Improvement Method ◽  
Piled Embankment

Soft soil reinforced by rigid inclusions under embankment is a soft soil improvement method, known as a piled embankment. It has been widely studied and applied over the world, since 90’s decade of the last century. The behavior of a piled embankment is mainly based on the formation of soil arching within the embankment and the negative skin friction around inclusion shaft. The paper investigates the mechanical behavior of a piled embankment to make clear the load transfer mechanism of the method. Additionally, some of the analytical methods in determining the stress transfer efficacy are presented.

scholarly journals Soil Arching of Piled Embankment in Equal Settlement Pattern: A Discrete Element Analysis

Symmetry ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1627
Author(s):  
Kangyu Wang ◽  
Jun Cao ◽  
Xinquan Wang ◽  
Yingjie Ning
Keyword(s):  
Slip Surface ◽  
Discrete Element ◽  
Settlement Pattern ◽  
Differential Settlement ◽  
Test Model ◽  
Soil Arching ◽  
Element Analysis ◽  
Arching Effect ◽  
Pile Cap ◽  
Piled Embankment

Soil arching, which occurs in the piled embankments, plays an important role in stress redistribution between the relatively soft subsoil and the stiffer piles. The formation of the soil arching depends on the differential settlement of the embankment fill above the pile and the subsoil. The soil arching effect is barely investigated in the literature from the perspective of differential settlement of piles and soils. Based on the discrete element method (DEM), this paper develops a classic trapdoor test model to investigate the differential settlement in piled embankment during the downward movement of the trapdoor, and to explore the formation mechanism of soil arching in equal settlement pattern by changing the width of the pile cap and the height of the embankment. Due to symmetry, only one section of the laboratory test model is simulated herein. It was found that the soil arching formed under the equal settlement pattern remained unchanged after a certain degree of development, and the height of the equal settlement did not change at 0.7(s-a), where s is the pile spacing, and a is the width of the pile cap. The height of the embankment (H) and the width of the pile cap (a) have a significant influence on the formation of the equal settlement pattern when the width of the trapdoor is kept constant. Both the decrease in “H” and the increase in “a” facilitate the differential settlement of the soil between the piles and the pile-soil, enabling the slip surface to develop upward gradually, thereby hindering the formation of the equal settlement pattern.

A theoretical solution for pile-supported embankments on soft soils under one-dimensional compression

2008 ◽  
Vol 45 (5) ◽  
pp. 611-623 ◽  
Author(s):  
R. P. Chen ◽  
Y. M. Chen ◽  
J. Han ◽  
Z. Z. Xu
Keyword(s):  
Skin Friction ◽  
Soft Soil ◽  
Closed Form Solution ◽  
Stress Transfer ◽  
Form Solution ◽  
Soil Arching ◽  
Foundation Soil ◽  
Negative Skin Friction ◽  
One Dimensional ◽  
Piled Embankment

Pile-supported embankments are increasingly being used for highways, railways, storage tanks, etc. over soft soil because of their effectiveness in accelerating construction and minimizing deformation. The stress transfer mechanisms among all of the components in a piled embankment, including the embankment fill, the piles and (or) caps, and the foundation soils, are complicated. In this study, a closed-form solution for one-dimensional loading was obtained taking into consideration the soil arching in the embankment fill, the negative skin friction along the pile shaft, and the settlement of the foundation soil. In the derivations, the piles, the embankment fill, and the foundation soil were assumed to deform one-dimensionally. This study investigated the stress concentration on top of the pile, the axial load and skin friction distributions along the pile, and the settlement of the embankment. Comparisons demonstrate that the results from this solution are in good agreement with those obtained using a finite element method. It is worth pointing out that this solution should be applied to the piles close to the centerline of the embankment and not to those near the toe of the embankment because of the two-dimensional loading condition near the toe.

scholarly journals Similitude Conditions Modeling Geosynthetic-Reinforced Piled Embankments Using FEM and FDM Techniques

2012 ◽  
Vol 2012 ◽  
pp. 1-16 ◽  
Author(s):  
Keith Jennings ◽  
Patrick J. Naughton
Keyword(s):  
Load Transfer ◽  
The Finite Element Method ◽  
Soil Arching ◽  
Absolute Value ◽  
Load Transfer Mechanism ◽  
Pile Cap ◽  
Model Geometry ◽  
Piled Embankment ◽  
Characteristic Trend ◽  
Piled Embankments

The numerical modelling of geosynthetic-reinforced piled embankments using both the finite element method (FEM) and finite difference method (FDM) are compared. Plaxis 2D (FEM) was utilized to replicate FLAC (FDM) analysis originally presented by Han and Gabr on a unit cell axisymmetric model within a geosynthetic reinforced piled embankment (GRPE). The FEM and FED techniques were found to be in reasonable agreement, in both characteristic trend and absolute value. FEM consistently replicated the FDM outputs for deformational, loading, and load transfer mechanism (soil arching) response within the reinforced piled embankment structure with a reasonable degree of accuracy. However the FDM approach was found to give a slightly higher reinforcement tension and stress concentration but lower reinforcement strain at the pile cap than FEM, which was attributed to the greater discretize of the model geometry in the FDM than in FEM.

Dynamic load moment exposure and spine function impairment

2009 ◽  
Author(s):  
William S. Marras ◽  
Steven A. Lavender ◽  
A. Sue ◽  
Ferguson Riley E. Splittstoesser ◽  
Gang Yang
Keyword(s):  
Dynamic Load ◽  
Function Impairment ◽  
Spine Function
Sign in / Sign up

Export Citation Format

Share Document