Experimental Study On The Seismic Behavior Of Perforated Brick Masonry Structure After Fire

The development of masonry structure has a long history in the world,and the masonry structure accounts for a large proportion in China's active building.This type of building not only has the use of functioin,some of these masonry structures also represent a cultural heritage,has become the city's spiritual wealth.However,according to statistics,the occurrence of fire in China has increased in recent years,and fire has great harm,resulting in a large number of property losses and casualties.Keeping the masonry structure from fire is a significant problem needed to be solved.However,the researches concerned with the fire resistance of masonry structure are only in the beginning stage in China.And there is no mature theory and method to solve the question of how to properly assess the safety and seismic performance of these masonry structures after fire.The research of damage diagnosis of perforated brick masonry structure after fire,and the seismic performance evaluation and reinforcement method of masonry structure,is the needs to guarantee the national economic construction and social stability,which has great economic and social benefits and a very important theoretical significance and engineering value.This paper will fill the gaps in the study of seismic performance of perforated brick masonry structures after fire.In this paper,perforated brick masonry wall was studied.At first,the experiment under standard fire and the experiment of low cycle loading after standard fire was conducted.Then a simulation study was carried out based on ABAQUS.The contents of this paper can be divided into several parts below:(1)The achievements refer to fire performance of masonry structures and the seismic behavior of masonry structure after strengthening at room temperature was concluded.(2)Taking the perforated brick masonry wall as the experimental object,the fire test of 6 pieces of wall specimen was carried out,and the influence of the fire time and the temperature distribution of the brick and mortar and the whole temperature distribution of the wall were investigated.(3)The finite element software ABAQUS is used as the platform to verify the results of the fire test and to study the variable parameters of the fire time.By studying the distance of the wall,establish the temperature calculation formula of the different positions of the fire wall at different times(4)Taking four pieces of perforated brick masonry wall after fire,two pieces of perforated brick masonry wall after fire with reinforcement and one piece wall under on fire as the experimental object,the low cycle test of 7 pieces of wall specimen was carried out.The effects of fire time,fire condition,cooling method and different reinforcement methods on seismic performance of masonry wall were investigated.(5)The finite element software ABAQUS is used as the platform to verify the results of the low cycle test,and the different reinforcement methods are analyzed by change the parameters.The effects of the way of sticking carbon fiber cloth,the number of adhesive sheets of carbon fiber cloth,the thickness of reinforced concrete mortar and the number of reinforced surface layers on the reinforcement effect of fire masonry wall were studied,and the suggestions for engineering designers were given,and provide suggestions for engineering designers.(6)Combined with the design specifications of masonry structure at home and abroad and the test results of this paper,the formulas for calculating the shear capacity of masonry walls with different ways to reinforce are obtained.