Shear Unified Strength Theory Research Articles

Calculation Analysis on Cracking Load of New Type Composite Wall

New type composite wall is the main bearing member in Multi-ribbed Slab Structure (MRSS), whose cracking load is an important parameter to determine the restoring force model and damage index of the wall. Based on the twin shear unified strength theory, when the influence of intermediate principal stress σ2 and SD effect of materials are considered, the study on low-frequency cyclic lateral loading experiment of wall is proceed and the practical formula for the wall’s initial cracking load is deduced. The practical computing formulas for the wall’s initial cracking load based on twin shear unified strength theory and maximum tensile stress theory are contrastingly analyzed. The results show that, comparing the calculated values based on the twin shear unified strength theory and the values based on maximum tensile stress theory, the former are more closed to the experimental values, and it can provide more accurate, economic and applicable results for practical engineering.

Unified Solution of Expansion of Cylindrical Cavity of Elastic-Brittle-Plastic Strain-Softening Materials with Different Elastic Modulus in Tensile and Compression

For strain-softening materials with different elastic modulus of tensile compression, two controlling parameters were introduced to take into account the different modulus and strainsoftening properties. By means of twin shear unified strength theory, unified solutions calculating stress and displacement fields of expansion of cylindrical cavity were derived. The effects caused by different elastic modulus in tensile and compression, different models and strain-softening rates on stress and displacement fields, development of plastic zone were analyzed. The results show the ultimate expansion pressure, stress and displacement fields and development of plastic zone vary with the changes of different elastic modular, different models and strain-softening properties.