Finite Element Simulation and Parametric Analysis of Composite Shear Walls with Steel Plates and Infill Concrete Under Axial Compression

The previous researches on composite shear walls with steel plates and infill concrete mainly focused on their seismic performance, but few researches on their axial compressive performance and stud stress characteristics. Also, the influences of some key design parameters on the ultimate bearing capacity and ductility of the wall are still unclear, which makes it difficult to determine the values of these parameters reasonably. On the other hand, the studs in the wall are used as shear connectors, which can make the steel plate and concrete work together, but the stress and deformation data of the studs are difficult to measure in the experiment. In order to solve these problems, the ABAQUS software is used to establish a finite element model of the composite wall under axial compression, and the accuracy of the model is verified by experimental data. Further, the aspect ratio, concrete strength, steel plate strength and stud strength are considered, and the parametric analyses are carried out to investigate the influences of these parameters on the mechanical properties of the wall.
In the finite element model, the concrete, steel plates and studs are simulated by C3D8R solid elements. Plastic damage is considered in the constitutive relationship of concrete, and the broken-line model is used as the constitutive relationship for steel plate and stud. A rigid body constraint is created to simulate the loading plate, and two reference points are set at the centers of the top and bottom of the wall model respectively. Then, the boundary conditions are assigned to the two reference points, and the load is applied downward to the top reference point. The accuracy of the basic finite element model is verified by the simulation results of initial stiffness, peak load and local buckling of steel plate, and then the four parameters mentioned above are adjusted to form 13 finite element models, and the load-displacement curves and ultimate loads of the walls with different parameters are obtained and compared.
The numerical results show that the load-displacement curves of the finite element simulation are in good agreement with the experimental results. Also, the local buckling of steel plate observed in the simulation is consistent with the experimental phenomenon. Therefore, the details of the finite element modeling are justified including the constitutive relationships of the materials, contact characteristics, boundary conditions and the parameter settings for the theoretical models, which can be used or referred to for the analysis and design of similar structural components. The three parameters of aspect ratio, concrete strength and steel plate strength have large influences on the ultimate bearing capacity of the wall. Also, the ultimate bearing capacity increases in an approximately linear trend with the increase of each parameter. However, the parameter of stud strength has almost no effect on the ultimate bearing capacity of the wall. Increasing the compressive strength of concrete will increase the ultimate bearing capacity of the composite wall more effectively than increasing the strength of steel plate. The smaller the aspect ratio is, the better the ductility of the wall is. Moreover, the stud stress is concentrated at the root. If the strength of steel plate is equal to that of stud, the root stress of stud will approximate its strength, and in other words, its shear resistance will be fully exerted.