Study On Seismic Performance Test And Lateral Stiffness Calculating Method Of The Frame Structure Strengthened By Composite Wall

In view of deficiencies of seismic stability of some existed frame structures, certain amount of these structures need to be strengthened without tearing down and the theoretical system of the multi-grid composite wall.Accordingly, this thesis proposed a strengthening method that applying the multi-grid composite wall to frame structures which need to be strengthened. Based on the experiments, numerical simulation and theory analysis, this thesis studied the strengthening effects, influence factors of strengthening effects, mechanical mechanism, seismic performances and the elastic lateral stiffness. The detailed works are as following:(1) By performing the low frequency cyclic loading tests on the half scaled model of composite walls of RC-autoclaved aerated concrete blocks, frame structure without blocks as well as the frame structure strengthened by the multi-grid composite wall, the destruction process, bearing capacity, hysteretic characteristics, rigidity decoration, energy dissipation, deformations and the load-strain curves of bras of each components were studied respectively. In addition, the strengthening effects and the action mechanism of the frame structures strengthened by the multi-grid composite wall were also studied.(2) By performing the the low frequency cyclic loading tests on the half scaled model with two different conditions, the general destruction types, destruction types of the blocks in the frames and the strain distributions of bars in each components, this thesis studied how various grid forms and layouts of blocks influence the seismic capacity of frame structures strengthened by the multi-grid composite wall and the strain distribution of bars in each components.(3)Based on the numerical model of the strengthening structures created by the ABAQUS software,the numerical results of stress distributions, bone curves and the stiff degradation were obtained. The obtained simulation results were compared to the experimental results and showed good agreements between each other. By changing the width of rib grids and the layouts of the created finite element model in ABAQUS,the conclusions of how the width and layouts of rib grids influence the structural mechanism were also obtained. Moreover, the reasonable width and layouts of rib grids were recommended based on the FE numerical results.(4) Based on the classical mechanic theory as well as compound material mechanics theory with the combination of mechanical characteristics of RC- aerated concrete composite walls, the stiff model under elastic stage was proposed.The lateral rigidity model of frame structures strengthened by the multi-grid composite wall and the action mechanisms between frame structure and the blocks were studied in this thesis. Meanwhile, the lateral rigidity model obtained above was further modified considering the width and layouts of the rib grids.Based on the experiments, numerical simulation and the theory analysis, this thesis studied the strengthening effects, influence factors of strengthening effects, mechanical mechanism, seismic performances and the elastic lateral stiffness. The thesis also provided the reasonable width and layouts of rib grids based on the study results mentioned above.Finally, the elastic lateral rigidity model was proposed in this thesis.