Analysis On Calculation Model And Bearing Capacity Of Ecological Composite-wall Based On The Twin Shear Unified Strength Theory

The ecological composite-wall structure is a new,energy-saving and assembled monolithic residential building structure with good seismic performance.The unique structural characters(using various materials and various nested members)of the structure make its related calculation theory and design method are different from those of other traditional structures.Based on previous study results,several aspects of multi-ribbed slab structure such as the constitutive equation and yield criterion of ecological materials,the elastic-plastic calculation model of multi-ribbed composite-wall,the calculation of the bearing capacity of the wall under axial compression and the cracking load of the wall have been studied in this paper according to the test results,theoretical analysis and numerical calculation based on the unified strength theory.The main works can be detailed as follows:1.To introduce the basic theory of the twin shear unified strength theory and to mainly study the mechanical properties of lightweight aerated concrete block according to five kinds of ecological filling materials studied and developed now by our team.According to the basic mechanical properties of different ecological filling blocks,the unified strength yield principles of ecological materials are deduced,and then the elastic-plastic constitutive equation based on twin shear unified strength theory are also obtained,which can provide a unified form solution for ecological composite wall filled with different ecological materials on calculating and analyzing.2.The twin shear unified strength theory is adopted to analyze the reason that the bearing capacity of multi-fibbed composite wall under axial compression is enhanced by the filling blocks and also to modify the previous formula for the bearing capacity of the wall under axial compression.Based on the experimental study of multi-ribbed composite wall under low-frequency cyclic lateral loading,the calculations formulas for the cracking load of the wall based on twin shear unified strength theory are established.It can be known from the results of comparative analysis that the values from the modified formulas for the beating capacity of the wall under axial compression and the cracking load of the wall are closer to the experimental values,which indicates the modified formulas can provide more accurate,economic and applicable results for practical engineering.3.According to analyze the rigid frame- equivalent oblique compression bar model of multi-fibbed composite wall,the width of equivalent oblique compression bar,based on the unified strength theory,is deduced.In addition,the rigid flame-oblique compression bar model with plastic hinges of a multi-ribbed composite wall is established,and the nonlinear dynamic reaction analysis is carded out.It can be known from the results of comparative analysis that the elastic-plastic calculating model of the wall based on unified strength theory agrees well with the true failure process and dynamic characteristic of the wall, which indicates the calculation model can provide more accurate and applicable results and is suitable for nonlinear numerical calculates analysis of ecological composite wall.