A Volume-Mass Constitutive Model for Unsaturated Soils in Terms of Two Independent Stress State Variables

As a part of the effort made to understand the behaviour of unsaturated soils, this work studies the shear strength characteristics of a cohesionless unsaturated soil. Generally, the determination of the shear strength of unsaturated soils is a great challenge to geotechnical engineers, both in terms of understanding it and the effort necessary to determine it. Matric suction is one of the stress state variables that control the shear strength of unsaturated soils. Therefore, the main aim of this study is to investigate the effect of matric suction on the shear strength characteristic of sand known commercially as Sand PR33. The shear strength behaviour of unsaturated sand is studied in this work using the constant water content triaxial test method with measurements of matric suction during the shearing stage. The tests were performed using the axis translation technique in such a way that the pore-air pressure was controlled while the pore-water pressure was measured during all tests.

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Stress State Variables for Unsaturated Soils—Consensus and Controversy

Developments in Geotechnical Engineering - Geotechnical Design and Practice ◽

10.1007/978-981-13-0505-4_7 ◽

2018 ◽

pp. 79-89

Author(s):

E. C. Leong

Keyword(s):

Stress State ◽

Unsaturated Soils ◽

State Variables

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Discussion of “Stress State Variables for Unsaturated Soils”

Journal of the Geotechnical Engineering Division ◽

10.1061/ajgeb6.0000596 ◽

1978 ◽

Vol 104 (2) ◽

pp. 303-304

Author(s):

Peter Bloch

Keyword(s):

Stress State ◽

Unsaturated Soils ◽

State Variables

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Progressive failure analysis of scarf-repaired composite laminate based on damage constitutive model

Proceedings of the Institution of Mechanical Engineers Part L Journal of Materials Design and Applications ◽

10.1177/1464420716666400 ◽

2016 ◽

Vol 233 (2) ◽

pp. 180-188 ◽

Cited By ~ 2

Author(s):

Qiuyi Shen ◽

Zhenghao Zhu ◽

Yi Liu

Keyword(s):

Finite Element ◽

Constitutive Model ◽

Composite Laminate ◽

Damage Mechanics ◽

Cohesive Zone Model ◽

Load Capacity ◽

Three Dimensional ◽

Zone Model ◽

State Variables ◽

Element Analysis

A three-dimensional finite element model for scarf-repaired composite laminate was established on continuum damage model to predict the load capacity under tensile loading. The mixed-mode cohesive zone model was adopted to the debonding behavior analysis of adhesive. Damage condition and failure of laminates and adhesive were subsequently addressed. A three-dimensional bilinear constitutive model was developed for composite materials based on damage mechanics and applied to damage evolution and loading capacity analyses by quantifying damage level through damage state variables. The numerical analyses were implemented with ABAQUS finite element analysis by coding the constitutive model into material subroutine VUMAT. Good agreement between the numerical and experimental results shows the accuracy and adaptability of the model.

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