Finally,an example is analyzed to show the characteristics of stress and strain distributions in the cracked and plastic regions and the influence of cracked region radius on them.

Results show that the instability of deep-buried hardrock tunnels is not only influenced by rock mass characters and loads,but also related with the ratio of the stiffness of elastic regions over the stiffness of plastic regions.

The paper comes from the actual project Tiantan East-station of Beijing No. 5 Subway. Inthe paper, the situation of displacement, stresses and plastic regions are studied.

Some plastic regions could be found and some dimples had been observed on the fracture surfaces of the solidification cracking of austenitic-ferritic weld metals.

According to the conditions that the stresses are continuous at the elastoplastic interface and that the radial strains are continuous at the plastic-cracked interface,the computational formulae to determine the radii of cracked and plastic regions are obtained.

And it is recommend that it be added some details of seismic design in potential positive plastic regions for frame structures in intensity 9. The minimum reinforcement ratios of the frame beam and column of seismic grade 1 given in Chinese code is reasonable.

The paper discusses the discontinuity behavior on the boundary between rigid and plastic regions in the dynamic analysis of rigid-perfectly plastic body.

This paper derives the general relationship on elastoplastic flow rule and Constitutive equations, which can take account of the uncontinuity in elastic and plastic regions and the nonlinearity of stress-strain response.

The method employing complex function to find plastic stresses is further developed. The stress concentration function and the demarcation lines between elastic regions and plastic regions are given under complex loading conditions.

Using the finite element method, this paper has studied the stress field and elastic and plastic regions around faults in different orientations under slowly loaded two dimensional pressure. The results are as follows : ①In the case of plastic or ductile deformation, conjugate shear angle of the deformation belts is usually larger than 45°;

Even in an initially purely elastic shaft two plastic regions with different forms of the yield condition may emerge simultaneously at the centre.

Plastic regions, fan zones, lines of discontinuity and stress states are analytically determined for obtuse wedges under the action of the prescribed kinds of loading.

This permits to ensure continuity between the elastic and the plastic regions during the loading process.

The other possibility is that, depending on the core radius, two plastic regions form one after the other or simultaneously, in the core and at the surface and join in the fully plastic state.

The evolved shear band patterns appear to be a strong function of loading rate, although the plastic regions beneath the loading surface have similarities in shape irrespective of loading type.

The present paper treats the compression of a rectangular block between two parallel rough plates as a problem in the theory of plane strain for perfectly plastic-rigid materials.At first, the plastic-rigid theory of plane strain was outlined, then, the solution to the present problem is briefly surveyed. In section 4, the case that is left out in the present literature, viz. when the width-height ratio lies between 1 and 3.64 for partially rough plates is solved. In this treatment, the coefficient...

The present paper treats the compression of a rectangular block between two parallel rough plates as a problem in the theory of plane strain for perfectly plastic-rigid materials.At first, the plastic-rigid theory of plane strain was outlined, then, the solution to the present problem is briefly surveyed. In section 4, the case that is left out in the present literature, viz. when the width-height ratio lies between 1 and 3.64 for partially rough plates is solved. In this treatment, the coefficient of friction ν is considered as constant along the contact surfaces. For eachμ, a critical value of the ratio w0/h is given. When w/hplastic region extends across the entire block, i. e. the unrestricted plastic flow is possible, before the frictional force is put to full use. In this case, there is no slip along the contact surfaces and the solution is the same as if the contact were perfectly rough.When w0/h

At a result of a theotetical analysis of the elastic, ability of shell, it is shown that when the effect of the restraint on the edges can be ignored, the buckling stress of a shell may be determined with the aid of the following formula: where Te is the total compresive stress in the direction θacting on a unit-length section of the shell Rθ+π/2, is the radius of curvature of the shell along the section; δis the thickness of the shell E is the modulus of elasticity of the material, and μis the poi- sson's ratio....

At a result of a theotetical analysis of the elastic, ability of shell, it is shown that when the effect of the restraint on the edges can be ignored, the buckling stress of a shell may be determined with the aid of the following formula: where Te is the total compresive stress in the direction θacting on a unit-length section of the shell Rθ+π/2, is the radius of curvature of the shell along the section; δis the thickness of the shell E is the modulus of elasticity of the material, and μis the poi- sson's ratio. The condition under which the effect of the edge restraint can be ignored is that where le is the span of the shell in the direetion θ. Some examples in which boundary condition have to be considered have been worked out, and the results are compared with the known results. Finally, an approximate expression is proposed for the tangential modulus of ela- sticity of the materiad, to thet the results of the present analysis can be extended to cover the elastic plastic region. A formula for use in practical structural calcu-lations is also given

In earthquake-resistant design, consideration must be given to the ductility of structures when subjected to seismic loading into the inelastic range. Research work in connection with this papar includes analysis of experimental results and development of a computer program for the calculation of the ductility factor of reinforced concrete flexural members. A new expression for the stress-strain relation was used in establishing the moment-curvature relations. Besides, in connection with displacement calculation...

In earthquake-resistant design, consideration must be given to the ductility of structures when subjected to seismic loading into the inelastic range. Research work in connection with this papar includes analysis of experimental results and development of a computer program for the calculation of the ductility factor of reinforced concrete flexural members. A new expression for the stress-strain relation was used in establishing the moment-curvature relations. Besides, in connection with displacement calculation the actual length of plastic regions and the actual distributions of curvature therein were also studied.