Eulerian finite element analysis of excess pore pressure generated by spudcan installation into soft clay

2012 ◽

Author(s):

Jiang Tao Yi ◽

Fook Hou Lee ◽

Siang Huat Goh ◽

Yu Ping Li ◽

Xi Ying Zhang

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Stress Analysis ◽

Pore Pressure ◽

Effective Stress ◽

Excess Pore Pressure ◽

Element Analysis ◽

Pore Pressures ◽

Excess Pore Pressures ◽

Excess Pore

The numerical modeling of spudcan penetration involves technical challenges posed by large soil deformation coupled with significant material non-linearity. The Lagrangian approach commonly used for solid stress analysis often does not work well with large deformations, resulting in premature termination of the analysis. Recently, the Arbitrary Langrangian Eulerian (ALE) and the Eulerian methods have been used in spudcan analysis to overcome problems caused by the soil flow and large deformation. However, most of the reported studies are based on total stress analysis and therefore shed no light on the excess pore pressures generated during spudcan installation. As a result, much remains unknown about the long-term behaviour of spudcans in the ground, which is affected by the dissipation of excess pore pressures. This paper reports an effective-stress finite element analysis of spudcan installation in an over-consolidated (OC) soft clay. The Eulerian analysis was conducted using ABAQUS/ Explicit, with the effective stress constitutive models coded via the material subroutine VUMAT. The results demonstrated the feasibility of conducting effective-stress finite element analysis for undrained spudcan penetration in OC clays. The paper discusses the flow mechanism, stable cavity depths and bearing capacity factors when spudcan installation occurs in various OC soils. It was found that the pore pressure build-up concentrates in a bulb-shaped zone surrounding the spudcan. The size of the pore pressure bulb increases with increasing penetration. The maximum excess pore pressure, which is generated near the spudcan tip, is predominantly controlled by the undrained shear strength at the tip level.

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The Effects of Geosynthetic-Reinforcement on Consolidation Behavior of Soft Clay Embankment under Step Construction

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.783.46 ◽

2018 ◽

Vol 783 ◽

pp. 46-50

Author(s):

Yu Cong Gao ◽

Rong Chen ◽

Dong Xue Hao ◽

Myoung Soo Won

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Pore Pressure ◽

Clay Soil ◽

Clayey Soil ◽

Soft Clay ◽

Excess Pore Pressure ◽

Calculation Results ◽

Consolidation Behavior ◽

Excess Pore

Geosynthetics–reinforced structures are widely used in embankments and walls. This paper presents the simulation of the embankment under load in order to compare the behavior of clay embankment with and without wrapping-facing-geosynthetics-reinforcement using finite element method (FEM) and to analyse the variation of behavior included of displacement and excess pore pressure under the different over-consolidation ratios (OCR). The calculation results show that embankment with higher OCR showing lower displacement compare to embankment with lower OCR. However, OCR isn’t very sensitive to the dissipation of excess pore pressure. Geosynthetics-reinforcements could reduce the displacement of embankment and accelerate dissipation of excess pore pressure after construction and surcharge. Gravel, geosynthetics-reinforcement and clay soil are properly combined, clayey soil is expected to be useful as embankment material.

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Numerical Analysis for Excess Pore Pressure Dissipation Process for Pressed Pile Installation

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.405-408.133 ◽

2013 ◽

Vol 405-408 ◽

pp. 133-137

Author(s):

Tai Quan Zhou ◽

Feng Tan ◽

Cheng Li

Keyword(s):

Finite Element ◽

Pore Pressure ◽

Excess Pore Pressure ◽

Soil Behavior ◽

Element Analysis ◽

Dissipation Process ◽

Pile Installation ◽

Finite Element Software ◽

Modified Cam Clay ◽

Excess Pore

The finite element analysis is performed on the excess pore pressure dissipation for pressed pile installation using the ABAQUS finite element software. The modified Cam-Clay model is used to model the soil behavior. The finite slide contact model is used to model the pressed pile installation process. Based on the geology stratum of soils and drainage conditions, the excess pore pressure dissipation process is analyzed using the proposed method. The initial excess pore pressure distribution along the pile depth and the pile radius direction is obtained. The excess pore pressure dissipation after 98 days is analyzed.

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Numerical Analysis of Staged Construction of an Embankment on Soft Soil

10.21203/rs.3.rs-437291/v1 ◽

2021 ◽

Author(s):

Ayesha Binta Ali ◽

Mehedi Ahmed Ansary

Keyword(s):

Finite Element ◽

Numerical Analysis ◽

Pore Pressure ◽

Soft Soil ◽

Excess Pore Pressure ◽

Element Analysis ◽

Staged Construction ◽

Modeling Software ◽

Degree Of Consolidation ◽

Excess Pore

Abstract The objective of this study was to predict the excess pore pressure and settlement of an embankment over soft ground, treated with vertical drain, through numerical analysis of staged construction. To carry out finite element analysis, numerical modeling software PLAXIS 3D was used. The practical demonstration was demonstrated by validating two case studies; the first one was a trial embankment at the Krishnapatnam Ultra Mega Power Project in Nellore, Andhra Pradesh, India and the second one was the Second Bangkok International Airport or Suvarnabhumi Airport, about 30 km from the city of Bangkok, Thailand. After the successful validation of the program, detailed finite element modelling of an embankment resting on soft soil was conducted. Moreover, the degree of consolidation and factor of safety were also determined. There was rapid dissipation of excess pore pressure and maximum settlement at the mid-height of the embankment. In contrast, the dissipation of excess pore pressure was very slow just below the embankment and it increased with the increment of the depth of the clay layer. Moreover, with the rise of the distance from the centre of the embankment, the dissipation of the excess pore pressure also raised and took less time, the settlement also increased.

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