In this paper, a three-dimensional Fast Lagrangian finite difference program (FLAC~3D), which can simulate large-strain deformation and progressive failure, is adopted to study the soil deformation and failure mechanism in EP shield tunnelling.

On the basis of the existing large-strain consolidation finite element analysis program (LSCFEA), by using the above theory, program to calculate moistening deformation is worked out and the large-strain description for wetted loess is realized.

This paper is an important part of the scientific project <<Large-strain description and numerical imitation analysis for hydrocompaction of loess>>(No.598780401) and the project of western transportation science & technology <> (No.200131881214). Based on large pooling infiltration testing of loess in situ, the characteristic of the infiltration of typical loess is discussed initially.

3D large-strain numerieal simulation of a hexahedral cell with microspherical void is conducted under different triaxial stress state parameter and Lode parameter conditions.

It is therefore of great theoretical and practical significances to make carefully and systematically studies on the theories of both small-strain and large-strain consolidation of layered soft clayey soils with non-linear and rheological properties.

It has been shown that the discrepancy between large-strain consolidation theory and small-strain one is increased with the increases of the compressibility of soil and the magnitude of loading.

The paper formulates a one-dimensional large-strain beam theory for plane deformations of plane beams, with rigorous consistency of dynamics and kinematics via application of the principle of virtual work.

Whereas in many investigations it is assumed that the fraction η of the plastic work transformed into heat is constant throughout the deformation process, the fraction η is here derived from thermodynamic considerations in a large-strain setting.

Large-strain and finite-rotation nonlinear behavior effects around the crack-tip are included.

Deformation microstructures during large-strain plastic working were studied in the pure Cu and Cu-1.5%Ni-0.3%P alloy, the original microstructures of which have been detailed in our companion publication.

The large-strain constitutive behavior of cold-rolled 1018 steel has been characterized at strain rates ranging from to 5 × 104 s-1 using a newly developed shear compression specimen (SCS).

In Composites, application of relatively low transverse strains or stresses can lead to locally large strains or stress in the matrix. It is therefore necessary to evalute the strain or stress concentration factors. A simple discussion of strain or stress magnification factors based upon a strength of materials type of approach is given by schulz in 1963. However, Foye 1966 solved the stress concentraton problem by finite element method indicating that the maximam stress concentration in the matrix is far less...

In Composites, application of relatively low transverse strains or stresses can lead to locally large strains or stress in the matrix. It is therefore necessary to evalute the strain or stress concentration factors. A simple discussion of strain or stress magnification factors based upon a strength of materials type of approach is given by schulz in 1963. However, Foye 1966 solved the stress concentraton problem by finite element method indicating that the maximam stress concentration in the matrix is far less than the one that may be inferred from the schulz approximate approach, stress function method are used by H Schuerch 1967 to determine the field of stress concentration produced by cylindrical inclusions in an other wise homgeneous matrix material subject to an applied stress transverse to the inclusion axis. More recently, L.C. Lee, H.D.Conway 1978 using the method by muschelisvili derived the bond stress for composite material reinforced with various arrays of fibers.Results from both schuerch and Lee-Conway also give stress concentration factors several times less than that by Sshulz.All those outined above are surveyed and another model of analysis be proposed to give an approximate solutions of this problem in this study.

Constant angular difference rotational mismatch method of Moire proposed in this paper is suitable for determining the strain states of different points in general non-homogeneous strain field. While measuring elastic or moderate plastic strains, only one analyzer grating with pitch equal to the specimen grating is necesssary and appropriate sensitivity can be attained complete strain solution of constant angular difference rotational mismatch method is derived in exact and simplified expressions. The former...

Constant angular difference rotational mismatch method of Moire proposed in this paper is suitable for determining the strain states of different points in general non-homogeneous strain field. While measuring elastic or moderate plastic strains, only one analyzer grating with pitch equal to the specimen grating is necesssary and appropriate sensitivity can be attained complete strain solution of constant angular difference rotational mismatch method is derived in exact and simplified expressions. The former of which is suitable for either small or large strains. Approach to determine the regions of different variables is proposed in order to measure strains during high sensitivity. The experimental device is designed and the stress concentration test by axial load is accomplished. Good agreement is found in a comparison of the experimental results to the theoretical solution.

The effect of large strain and high triaxiality farours the initiation and growth of voids in many ductile materials. This causes volumetric dilatation in the plasticity. So, dilatational plastic constitutive equations are proposed as eq. (1) and the inverse form in eq. (4). In which, Etm(p) is the volumetric plastic tangent modulus. When Etm(p)→∞, then yields the conventional Prandtl-Reuss equations. In eqs. (5) and (6) the criteria of strain softening are given, when either of these condition is met Ete(p)...

The effect of large strain and high triaxiality farours the initiation and growth of voids in many ductile materials. This causes volumetric dilatation in the plasticity. So, dilatational plastic constitutive equations are proposed as eq. (1) and the inverse form in eq. (4). In which, Etm(p) is the volumetric plastic tangent modulus. When Etm(p)→∞, then yields the conventional Prandtl-Reuss equations. In eqs. (5) and (6) the criteria of strain softening are given, when either of these condition is met Ete(p) or Etm(p) turns to negative. The six material constants Ete(p), Etm(p), λe,σce,λm and σcm can be calibrated and justified by using the necking tests of axisymmetric bars (with and without notches) and the computer simulation technique. The importance of the dilatational plastic effect and the strain softening is delineated in figs. 5,6,7.