Experimental Study On Shear Failure Mode Of 290 Concrete-Block Casting Wall Under Low-Cyclic Loading

Reinforced masonry structures have been widely used in the world, due to their advantage in so-called four-savings and environmental protection and conforming to the policies of improving wall materials. In recent years, our university promoted concrete-block casting wall structures (CBCWS) on the basis of reinforced masonry as their good mechanical properties and economic benefits, which adapt the characteristics of China's current construction , meet the development philosophy of construction simple and more easily to ensure the quality and play more and more important role in small high-rise buildings. But, our country started the research on reinforced masonry structures relatively late and the corresponding specifications in the design codes are still not perfect, which restricts the application of CBCWS in terms of seismic regions. Under the background of the research on 100-meter reinforced concrete block high-rise structures, this dissertation carries out the experimental study on the shear performance of 290mm thick CBCWS and provided an experimental basis for designing and building this type of strcuture.This dissertation: 1. conducts the low cyclic loading experiment of 4 pieces of 290 CBCWS; 2. simulates the shear seismic failure mode of the wall; 3. draws the characteristic load values and the corresponding displacement values of walls; 4. analyzes the mechanical performance of reinforcement at various working stages of tested walls. By analysing restoring force features of the walls, this paper obtains skeleton curves, stiffness degradation curve, restoring force model, deformation and energy dissipation capacity and so on, when compared these performance parameters with those of 190 and 240 thick CBCWS. Hence, seismic performance evaluation could be provided though the analysis above. By changing the horizontal reinforcement ratio and vertical pressure, it analyzes the shear performance influence of the two factors; the analytical results show that horizontal reinforcement contribution in shear load-bearing capacity does not keep increasing with the increase of horizontal reinforcement ratio.Based on experimental results, this paper analyzes all kinds of effects on the shear load-bearing capacity of reinforced concrete masonry shear wall, and compares the experimental results with calculated ones usinf the shear capacity calculation formula in Code for design of masonry structures(GB 50003-2001) and Code for design of concrete structures(GB 50010-2002). The analytical results show that in case of higher horizontal reinforcement ratio and higher axial stress, the values calculated by the shear capacity calculation formula in Code for design of masonry structures(GB 50003-2001) is higher than the corresponding experimental results. Therefore, CBCWS could be used to construct high-rise and super-tall buildings, as it has the relatively shear load-bearing capacity higher than that of reinforced concrete shear wall and better relatively seismic behavior.This dissertation using the FEA program ANSYS. When compared with the experimental results of 4 shear wall panels.The analytical results show that to a certain extent, the FEA could be considered to reflect mechanical properties of CBCWS, which can be used to simulate shear performance of CBCWS.