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

The reinforced masonry (RM) structure was widely in the world used. During to their advantage in four-savings and environmental protection and conforming to the policies of wall materials reforming, In recent years, concrete-block casting wall structures (CBCWS) are rapidly developed as their good mechanical properties and economic benefits, which adapt the characteristics of China's current construction .In order to make this system to be used in higher building, the thicker wall must be studied. Under the background of the research on 100-meter reinforced concrete block high-rise structures, this dissertation carries out the experimental study on the bending performance of 290mm thick CBCWS and provided an experimental basis for designing and building this type of structure.According to experiment ,the bending failure model of six pieces of CBCWS under combined compress, bending and shear force is studied,and the failure mode, the energy dissipation indicator and rigidity degeneration under low-cyclic loading are obtained. The experiment verifies that there are four stages during the whole bending failure process: elastic stage, plasticity stage, plastic stable stage and softening stage. This paper gets three linear stage of skeleton curve model according to the tests, and fits the rigidity degradation curve, and then, this paper suggests using the modified Clough hysteresis rules. all of these show that CBCWS have the similar performance with the RC shear wall.Based on the experiment data, this paper tests the flat section assuming by reinforcement masonry shear wall, and then doing analysis about limit state, standard method, bending moment-curvature, which is based on normal sections respectively. We can get the ratio of analysis test value and the calculated value. The results show that it is reliable to calculate the bearing capacity based on the theoretical calculation of flat section assuming, and it means this design method is applicable. The 290mm CBCWS indicates good strength, stiffness, ductility energy dissipation capacity.