抄録
It is thought that the previous equation for the flexural ultimate strength of shear walls with an opening has enough accuracy. But, it was found that the calculation results for flexural strength ratio of shear walls with an opening to shear walls without an opening by the previous equation became often bigger than experiment and FEM analysis results. So, the flexural resistance mechanism of shear walls with an opening was investigated by FEM analysis, and the proposed method for the flexural ultimate strength for shear walls with an opening was developed.
By experiment and FEM analysis results, the following knowledge was obtained.
1. The flexural strength is influenced by position, width and height of door shaped opening.
2. The loading moment ratio of the tensile region decreases, if an opening is at the compressive side edge of wall panel.
Assumptions of the proposed method are the following.
1. The flexural moment at leg of wall is shared by the flexural stiffness of the tensile region and compressive region, and the flexural stiffness composed of the axial stiffness of the tensile region and compressive region.
2. If the tensile force of the tensile region becomes bigger than the axial force loading before horizontal force loading, the flexural stiffness of tensile region is decreased.
3. The flexural cracking strength can be calculated by the moment sharing ratio proposed for calculating the flexural ultimate strength.
It was found that the calculation results for flexural strength ratio of shear walls with an opening versus shear walls without an opening by the proposed method corresponded well with experiment and FEM analysis results.
