Effect of shear-span ratio and vertical reinforcement ratio on the failure of geometrical-similar RC shear walls

The purpose of this study is to investigate the size effect on reinforcement concrete (RC) shear walls having different shear span ratios and vertical reinforcement ratios by the two-dimensional (2D) meso-scale simulation method. Firstly, the meso-scale simulation method was verified by the existing test data. Then, the effects of shear span ratio and vertical reinforcement ratio on the mechanical properties of RC shear walls with different structure sizes were studied by using this method. The results show that: 1) The failure mode of shear walls changes from shear failure to bending failure with the increase of the shear span ratio. 2) With the increase of the shear span ratio, the shear capacity of the shear wall decreases and the ductility increases, which leads to the weakening of the size effect. 3) The increase of the vertical reinforcement ratio has a slight increase in the shear capacity of the shear wall, but has almost no effect on the ductility and size effect. In addition, based on the established size effect law which can reflect the quantitative effect of horizontal reinforcement ratio and axial compression ratio, a new size effect law for RC shear wall was proposed considering the quantitative effect of shear span ratio.