Experimental Study On Seismic Behavior Of Short-span Coupling Beams Of Shear Walls

Coupling beams are important elements in coupled walls. They are ligaments for passing force between single shear walls. So the strength, stiffness, ductility and energy dissipating capacity of coupling beams can affect the performance of shear walls directly. The small-span-to-depth-ratio coupling beams are usually adopted in the coupled walls or core-walls to assure the lateral stiffness of structures. Test show that if these kinds of coupling beams are designed with seismic design methods of normal frame beams, the premature shear failure can not be avoided, so the ductility demand of structures can't be satisfied. The Code for Design of Reinforced Concrete High-rise Structure (JGJ3-2002) should be improved because the controlling conditions on shear-compression ratio of the proposed scheme are too strict and its displacement ductility is too small. So far domestic and foreign researchers have not yet found out an effective reinforcement scheme for convenient construction and guaranteeing the occurrence of shear failure after coupling beams attaining displacement ductility required.Aiming at this important problem to be urgently settled in engineering design, the research group of the authors has carried out a series of test on small-span-to-depth-ratio coupling beams. Firstly, the Master Zhang Binbin's tests further verified that the design methods in The Code for Design of Reinforced Concrete High-rise Structure (JGJ3-2002) can not satisfy seismic requirement. At the same time, our research group found that some acceptable improved reinforcement scheme suggested by domestic and foreign researchers can still not attain satisfied ductility performance.At the basis of the summary of reinforcement scheme already put forward, a reinforcement scheme with good applicability in engineering, namely the reinforcement scheme of adding diagonal bars and rhombic inclined bars on the basis of traditional reinforcement, have been given. The tests proved that the small-span-to-depth-ratio coupling beams with this reinforcement scheme can obtain well ductility and plastic energy dissipation capacity.To perfect the research, the main study work of this thesis is as following:1,Prove the seismic resistance behavior of this reinforcement scheme with high shear-compression ratio through more tests.2,Analyze the results of tests on couple beams with new reinforcement scheme, to make clear the load characteristic of diagonal bars and rhombic inclined bars and the...