The Research Of Stairwell Stiffness's Effects On The Seismic Performance Of Reinforced Concrete Frame

Currently,the existing structural design of different structural systems, such as masonry structure,frame structure and wall structure,don't consider the staircase' impact and the seismic design of staircase. The designing analysis and calculation of staircase structure is simplified. The structural design punches hole in the floor slab of staircase and apply the vertical load of staircase to the beams aroud. The staircase components is calculated individually.In the frame structure,the staircase works as the role of diagonal bracing, which can increase the stiffness of the main structure,shear force of story, and reduce the frame structure's lateral displacement. The staircase will increase the internal forces of surrounding frame components. Under the earthquake,the internal forces of staircase components are increased significantly.Based on these two points,this paper designs six reinforced concrete frame structures according to the codes. And then it comes to take the staircase structure into calculation and analysis under frequent earthquakes and rare eathquakes.This paper' main tasks include:(1)To compare the different influence of staircase structures on frame structure,when the location of staircase structures and layout of the frame structures is different.(2)To compare the internal forces'changes of structure's components,under or free from earthquakes.(3)To analyze,under rare eathquakes,the overalll forces and lateral displacement of six frame structures.(4)To propose some suggestions on the current design methods of staircases,and of the staircase-considered frame structures.