At present, DEM is unsuitable for analyzing reinforced concrete (RC) shear wall structures due to the lack of a shear wall model. In this paper, the macro-scale multi-spring shell element model (MSSEM) based on the DEM is proposed. The key model parameter on the computational results is an important aspect of this study.
In the MSSEM, a shear wall is meshed as an assembly of quadrilateral shell elements. Adjacent elements are connected by multiple springs to describe the axial-flexural and shear behaviors between elements. Several quasi-static experiments on RC shear wall specimens are simulated to evaluate the feasibility and effectiveness of the MSSEM and to quantify the influence of key modeling parameters, including boundary condition, element size, element aspect ratio, and number of springs.
The effectiveness of the MSSEM is verified. When boundary conditions are rigid boundaries, the longitudinal elements of the models should not be divided too much and the effects of the element size, and element aspect ratio on the calculation results are found to be inconspicuous. It is advised that the element size be 1/5 to 1/10 of the wall height and width, respectively, and that the use of 7 × 2 springs between adjacent elements is sufficient to meet the accuracy requirement.
The proposed MSSEM can obtain ideal results with a small number of elements. Additionally, MSSEM adopts a uniaxial constitutive model to reflect the mechanical properties of a two-dimensional shear wall, also yielding ideal results.
