Three Parameters Of Twin τ~2 Strength Theory And It’s Application

Rock, concrete and other materials are widely used in the engineering construction of brittle materials, in civil engineering, water conservancy and mining engineering, the strength of rock and concrete and other materials is an important parameter for engineering design. But because of the rock, concrete and other materials are often in a more complex stress state when they in the work, so the strength of this kind of engineering materials research has important theoretical and engineering practical significance. Many scholars put forward many different strength theories to analysis the damage of engineering materials. Analysis of the mechanical characteristics of the material and structure not only ensures the strength of the structure, but also avoid the waste of materials and thus reduces the cost of economy by adopted reasonable strength theory. However, in the complex stress state, there is no one kind of strength theory is suitable for the damage problem of all materials, so it is necessary to study the strength theory.First, on the basis of twin τ2 strength theory, considering the intermediate principal stress, isotropic and anisotropic materials influence on damage of materials, puts forward a new strength theory. Draw the π plane and limit trace of this theory, and compared with other strength theories.Secondly, using the three parameters of twin τ2 strength theory, analysis the strength problem of many kinds of stress state of part of rock and concrete under triaxial extruding, triaxial extrusion, biaxial compression, really triaxial and the composite of σ-τ, it also present a comparison with the experimental data of rock and concrete materials. The results show that, theoretical predictions and experimental results are basically consistent, different materials correspond to different limit stress ratio α and β, which corresponds to different material in different strength theory.Finally, using the three parameters of twin τ2 strength theory analysis uniformly distributed load of thick wall cylinder ultimate stress, considered properly the whole changing process of elastic-plastic materials, the analytic solution of the whole elastic-plastic deformation process is obtained which is suitable for thick-wall cylinder of differential strength in tension and compression.In this paper, the theoretical analysis of rock, concrete and metal materials shows that the new strength theory is proposed in this paper is feasible, and it is a supplement to the theoretical system of strength.