Study On Multi-Story Structure’s Equivalent Stiffness And Cross-section Bearing Capacity Design Method For Multi-Ribbed Composite Wall

Multi-ribbed composite wall is composed of a multi-ribbed composite wall plate and cast-in-site connection components. Due to the complicated constitution of the multi-ribbed composite wall and the complexity of bending and shear deformation of multi-story structure, the computer-aided solution for lateral stiffness of the multi-story structure with multi-ribbed composite wall is more complicated than that of the high-rise structure with multi-ribbed composite wall or other conventional structures. In addition, the equation governed the cross-section bearing capacity of the multi-ribbed composite wall is so complex that it is difficult to be applied in the structure design. Thus, it is necessary to conduct in-depth study of the computer-aided solution for lateral stiffness of the multi-story structure with multi-ribbed composite wall and the design method of the cross-section bearing capacity of the multi-ribbed composite wall in multi-story and high-rise structures.Based on theory analysis and numerical simulation, the equivalent method as along with the discussion of influence factors of lateral stiffness for the multi-story structure with multi-ribbed composite wall is studied, and the calculation method of the cross-section bearing capacity of multi-ribbed composite wall in multi-story and high-rise structure is also analyzed with the factors that influence its values. The main research content as follows:(1) The equivalent models of the multi-ribbed composite wall are established through the methods of area equivalent, continue equivalent, composite equivalent and EA equivalent. And the deformation is simulated using the finite element software. Comparative analysis is also conducted between different methods, and the results demonstrated that the lateral stiffness of EA equivalent model is more accurate.(2) Based on the finite element numerical analysis model of the multi-story multi-ribbed composite wall, the ratio of height to width, the length and reinforcement ratio of side connecting column, the division of lightweight concrete block, the dimension of rib and beam, and the middle connecting column of the multi-ribbed composite wall are analyzed about influence on the value of the multi-ribbed composite wall lateral stiffness. A reasonable range of these influence factors is determined through the finite element simulation.(3) A check design method is proposed for calculating the cross section bearing capacity of the multi-ribbed composite wall, and a MATLAB program is organized based on this design method. The method is verified to be correctness and feasibility when compared the calculation results of program with theoretical formula.(4) Based on the Nu-Mu interaction curve of multi-ribbed composite wall with the check design method, the dimension and reinforcement ratio of boundary restraints, the dimension of rib, the strength grade of lightweight concrete block, the strength grade of concrete, and the division of lightweight concrete block are analyzed about influence on the value of cross section bearing capacity of the multi-ribbed composite wall.