Study On Seismic Damage Mechanism Of Masonry Spandrel Walls

The influence on seismic performance of spandrel walls in masonry structures is a problem which is always been ignored. It is proved by the phenomenon of demolishing and transforming spandrel walls and the application of fluttered windows in present practice. It is thought that the spandrel wall is not the main bearing member, so it does not pose a threat to the safety of structures. However, the spandrel wall has a strong effect on the earthquake resistant performance of structures, and it is relevant to structural seismic safety.The real earthquake damage of masonry structures indicates that the damage of spandrel walls also affects the realization of the seismic fortification goal which is"without damages under minor earthquake and without collapsed under great earthquake". Nevertheless, the code for seismic design of buildings only makes a request for the seismic check of walls between windows, while it does not require seismic check on spandrel walls. So it is quite necessary to have a study on the seismic damage mechanism of the spandrel wall and propose some measures for it to resist earthquake.The aim of this research is to study the seismic damage mechanism of spandrel walls, that is, how the earthquake load transfers to the spandrel wall, in what way the spandrel wall is damaged under the earthquake load, and in which circumstance the spandrel wall will be damaged. Also, the measures which can ensure the spandrel wall to be favorable for earthquake resistance will be put forward.Firstly, the earthquake damage of the spandrel wall is introduced, through which it is pointed out that the spandrel wall has a strong influence on the seismic performance of structures and it is relevant to the seismic safety of buildings, so it is necessary to study its seismic damage mechanism, and propose measures to make sure the spandrel wall to be in favor of the structural seismic resistance. Subsequently, seismic check was made on two real structures based on the current code for seismic design of buildings and it is indicated that there is deficiency in the code in guaranteeing the seismic performance of the spandrel wall. And then, combining the real earthquake damage of spandrel walls, the seismic damage mechanism of spandrel walls is analyzed, including the transfer path of earthquake load, the reason for the crack of spandrel walls under earthquake load, and the circumstance in which the spandrel wall will be damaged. Afterwards, the influence of the spandrel wall on the structure's seismic performance is analyzed. And at last, the earthquake damage of masonry walls is simulated by the finite element analysis software, ABAQUS, the failure law of the spandrel wall under earthquake is found and some resistant measures which are beneficial for the earthquake resistant capability of the structure are proposed.