QR Method For Elasto-Plastic Analysis Of RC Shear Walls

As a construction unit resisting side force, RC shear walls are used widely in tall buildings. Usual analytical method of shear walls is based on elastic assumption or limit analysis. But oweing to the complexity and particularity of RC materials, the structural analysis based on linear elastic theory gradually cannot fully reflect the real working state of upper shear walls developing at a tremendous pace, thus nonlinear analysis plays a key role more and more.QR method is taken as a computing method for nonlinear analysis of shear walls, adopting the basic thinking way of conventional FEM in discretization, decreasing the unknown numbers and computing quantum in nonlinear and complex analysis by inducting a transfer relationship.Firstly, the new spline basic function is deduced according to the fundamentals. Combining it with power series, the paper worked out the displacement function, and improved shear walls' elastic computation format with QR method. The program is designed in MATLAB to analyze some examples, compared with ANSYS. Then, the RC material's constitutive relationships and yield criterions are determined in the nonlinear analysis according to the stress properties of shear walls. Basing on the fundamentals of elasto-plastic mechanics, the paper worked out the explicit expression of stress-strain relationship following the pre-researches. Introducing QR method to RC's disposing of cracks and stress releasing, the author derived the specific computing format basing on the principles of QR method, and developed the corresponding program with visualized Graph User Interface (GUI) . Some project examples are analyzed with it. Comparing the results with that of ANSYS or experiment in detail, the paper concludes that the method has gathered all the merits of strong adaptability, few unknown numbers, high precision and simple computation. It is valuable not only in theory but also in practice.