Masonry Structure Building Stair Of Seismic Response Analysis

In our country,masonry structure material is a kind of traditional architectural structure system, and relative to the concrete structure, because of its easy procurement, low cost, good durability and thermal insulation, is widely used in the urban and rural architectures in our country. With the continual appearance of various new materials, masonry structure will have promising application and development space in our country. Stairway is an important way to flee for life in the earthquake and previous earthquake damage indicates that the damage of staircases in masonry structure is more serious than that of the main structure.This thesis will take ordinary parallel stair of double-way for example to conduct time history analysis under infrequent earthquake. In this thesis, I will establish a separated and a unitary staircase model, respectively, in the construction of two-stairs and two-way reinforcing steel. Studies have shown that:in the construction of two-stairs and two-way reinforcing steel, the maximum displacement of the stairs happens in the tower place constructional column place stress value is bigger than other place, concrete not achieve its compressive strength value. Under the same seismic waves, the unitary staircase, since it suffers huge seismic energy infused from the whole building and the reinforcing steel and the concrete reach their limit bend, will go into the plastic. Therefore, it’s dangerous to design stairways under static condition. When infrequent earthquake happens, the structural damage is mainly laid in the ladder beams and the surrounding concrete, the bench plate tension zone, the top of the structural column and the junction of the structural columns and ring beam. All the above damages are caused by the inadequate concrete tensile stress. The separated stairway go into the location of the plastic moment and location approximately the same with that of the stairs to participate in the overall structure of the work injury. I will conduct time history analysis and calculation by changing the layout of the location of the stairs. Studies have shown that:wherever the stairway locates, the plate reinforcing steel bar will go into plastic; the concrete will go into plastic only when the stairway locates at the end of the architecture; when the staircase is located at the corner of the stairwell in position1, the wall in masonry structure will be the first part to go to plastic failure. At the three positions, the damage of the stairwell wall is reduced gradually from the bottom to the top. The wall happened typical "X" type shear damage.Hope to provide some theoretical reference for the future research work by the conclusions of this research work.