The Analysis And Research For Torsional Of Steel-Reinforced Concrete

Because of its advantages such as high bearing capacity and stiffness as well asexcellent seismic performance, steel reinforced concrete structures are usedincreasingly more for practical engineering. In our country, the research on thecomponent torsional mechanism developed quite late. At present, the performance ofthe steel reinforced concrete under torque is not fully understood and very few peoplehave done some research on the torsional mechanism. To carry on theoretical analysisof the performance for steel reinforced concrete under the combined forces of bending,shear and torsion has an important practical meaning as well as a broad applicationprospect.In this thesis the failure mechanism and calculation method of concrete structureunder pure torsion are introduced first. Eight numerical models for steel reinforcedconcrete which subjected to pure torsion are established by ANSYS program, and theanalysis results are compared to the experimental results. It was found that ANSYScan simulate the behavior of the member under pure torsion with reasonablenumerical model. The stress distribution of the concrete, bar and steel as well as thedevelopment and form of the cracks are analyzed in typical load step. The influence ofsteel size for torsional performance of member is discussed. Besides finite elementmodels for steel reinforced concrete under various torsion-bending ratio areestablished for nonlinear analysis, it is found that member's bending capacitiesreduced when the members subjected to torsion. The torsional performance of RC,SRC, and hollow composite members which have the same size and reinforcement arecompared each other. It is found that the torsional performance of hollow compositemember is better than the other two members.Base on the computational theory of thin-wall member and reinforced concretemember and combining with the result of experiment and finite element analysis, asimplified calculation formula of crack torsion strength and ultimate torsion strengthfor SRC and hollow composite member is proposed. The result of calculation arecompared to the result of experiment.