Experimental investigation and numerical simulation of masonry walls designed in different versions of Chinese codes

Masonry structures built in different years according to different Chinese seismic design codes are still widely distributed in China. In order to study the differences in seismic performance of these masonry structures, pseudo static tests are carried out on three masonry walls designed according to different versions of codes, and a numerical simulation method for the masonry walls is established. First, three masonry walls are designed according to different versions of codes, which adopt different confined measures. Pseudo static tests are then conducted on these three masonry walls to obtain their damage development law, hysteresis response, skeleton curve, and energy dissipation capacity, etc. Finally, the numerical simulation method for the masonry walls is established based on the cohesive surface interaction. The results show that the specimen Q-1, which is designed according to TJ11-78 and GBJ 11-89, exhibits sliding failure, and the specimens Q-2 and Q-3, which are designed according to GB50011-2001 and GB50011-2010, respectively, exhibit shear failure. The confined column can effectively prevent sliding failure of masonry walls and make the hysteretic curve fuller. Increasing the longitudinal reinforcement strength and reducing the stirrup spacing in the confined column can increase the ultimate bearing and deformation capacity, as well as the fullness of the hysteretic curve. The proposed numerical simulation method can accurately simulate the cracking and hysteresis response of masonry walls with a skeleton curve error of less than 5%.