Analysis On Seismic Performance Of Masonry Structure With Some Large Holes In Bottom-External Longitudinal Wall

In seismic region,the appropriate structure types of building with ground floor shop or garage are generally as follows: masonry structure with some large holes in bottom-external longitudinal wall,masonry structure with bottom-partial RC frame,masonry structure with bottom-partial RC wall etc.This article starts from a residential building(multi-story masonry structure)in a residential district and design masonry structure with some large holes in bottom-external longitudinal wall(model 1),masonry structure with bottom-partial RC frame(model2),masonry structure with bottom-partial RC wall(model 3).ABAQUS is used in this article,and three finite element models were established to compare the damage cloud image,The strain of column section and beam section and the interlayer displacement angles of the structures in order to study the seismic performance of the three models.Through the above analysis,the following results are obtained :(1)The numerical method is a better tool for simulating the masonry building earthquake response process,and the seismic weak parts are found in the first and second floor of the three models.The inclined shear cracks were apparent on longitudinal walls of the fist and second floor,and horizontal flexural cracks were apparent on longitudinal walls of the fist floor.(2)The seismic force is based on principle of stiffness distribution.Stiffness is discrepancy obviously among longitudinal walls of the three models,and the internal longitudinal wall which had the greater stiffness damaged firstly and severely.Meanwhile,the seismic and gravity loads were transferred to the two relatively weak external longitudinal walls.(3)Under 7 degree(1.0g)major earthquake,the plastic damage,The strain of column section and the interlayer displacement angles of masonry structure with bottom-partial RC frame(model 2)are similar with masonry structure with some large holes in bottom-external longitudinal wall(model 1).Plastic damage appear on the longitudinal wall of masonrystructure with bottom-partial RC wall(model 3),but there are not plastic hinges at the bottom columns.The performance level of the three models is evaluated with different performance indexes and research shows that:masonry structure with bottom-partial RC frame(model 2)is in the transitional stage between slight damage and moderate damage,masonry structure with some large holes in bottom-wall(model 1)is in a state of slight damage,masonry structure with bottom-partial RC wall(model 3)is in the transitional stage between undamaged and slight damage.(4)Under 7 degree(1.0g)major earthquake,because window-hole is irrational,plastic hinge is formed at the second-floor-column(A-1)of masonry structure with some large holes in bottom-wall(model 1).Because vertical stiffness is mutational,plastic hinge is formed at the bottom of the second-floor-column(A-1?A-9)of masonry structure with bottom-partial RC frame(model 2).