Seismic Performanceanalysis And Design Of Different Forms Of Coupling Beams

Coupling beams play an important role in shear walls. However, it is difficult fortraditional coupling beams with small span-to-depth ratio to satisfy the requirementsfor bearing capacity, stiffness and ductility at the same time. To solve this problem,many different forms of coupling beams have been proposed and investigated.Based on previous studies and work, this paper examines the disadvantages andinvalid assumptions associated with the existing design methods of coupling beams,In addition, this study also explores new forms of coupling beams. The mainconclusions of this study are as follows:(1) The first part of the work focuses on the steel-concrete composite couplingbeams, which have been rarely studied experimentally and for which there is a lack ofstandard design method in the code of our country.28shear wall models underunilateral load have been developed using ABAQUS. A robust design method ofsteel-concrete composite coupling beams with small span-to-depth ratio was proposedin this paper base on the analysis of the crack feature, ductility performance, thereasonable embedment length, the space of the nominal transverse reinforcement, andthe bearing capacity contributions from the steel and the concrete.(2) The second part of the work focuses on the diagonally reinforced couplingbeams. First, the range of the ratio of the transverse renforcement to the diagonalreinforcement recommended in the code of our country was questioned. Wehypothesize that an optimal value for this ratio may exist under certain conditions. Totest this hypothesis,35shealwall models under unilateral load have been developedusing ABAQUS. Based on the analysis of the crack feature, the ductility performance,the rigidity degradation, and the energy dissipation capacity, a new range of values forthis ratio has been determined. In addition, we also obtain the optimal value undersmall span-to-depth conditions, which leads to an optimization for the design method.(3) Inspired by the coupling beams which are embedded with diagonal columns,a new form of coupling beams is proposed which is referred to as multilayertransverse reinforcement-diagonal reinforcement coupling beams. Similar to themethods mentioned before,35shearwall models under unilateral load have beendeveloped using ABAQUS. The seismic performance of the new form of couplingbeams is investigated using different parameters and is compared to that of the diagonally reinforced coupling beams, based on which a standard design method ofthe new form of coupling beams is proposed.