Nonlinear Analysis Model Of Concrete Core Wall With Concealed Bracings

Influence of the earthquake in China is one of the most serious countries all over the world. Under such geological conditions and natural environment, how to make sure of avoiding the structure from collapsing in the earthquake disaster or keeping its repairable capacity when the structure damaged has become the urgent problem to the researchers in China. The results indicates that core-shear wall structure system shows better integrity, stiffness and stable capacity than the other structure systems such as masonry or frame system in seismic performance.Based on the research of domestic and abroad experiment data, and according to the reference of existing relative literature, the research on the core-shear wall structure system as the following aspects is made in this article:Firstly, established the Separated entity model according to the samples in the experiment of 3-story concrete core-shear wall with concealed bracing under cyclic loading which executed by professor Wanlin Cao, Beijing University of Technology,and his PHD Xuanming Huang in 2004, which use SOLID65 element to simulate concrete, separately use LINK8 and BEAM188 element to simulate distributed and concealed bracing rebar.Secondly, the comparison is made with 3 core structure finite-element models and analyze the simulation results. In addition to the element which is used to simulate rebar, the 3 models have the same scale in geometry and parameters of materials as well. By comparing the seismic capacities, such as load-displacement curves, stiffness, angular-displacement curve, the initial stiffness, cracking load, ultimate load and ultimate displacement of the 3 finite-element models, the applicable conditions of each model, and their advantages and inadequate of simulation analysis is concluded in this article.Thirdly, according to the results of previous researches, model called CT-1 which used the regular configuration of rebar in coupling beams and model called CT-2 which used the 45 degree configuration of rebar in coupling beams are established. In the above models, 3-dimensional entity element SOLID65 which is supported by ANSYS to simulate concrete and 3-dimensional line element LINK8 to simulate separated rebar are selected. The nonlinear analysis under monotonic load to study and compare the seismic performances of the regular and 45 degree are conducted, two different rebar configurations, in coupling beams.Finally, research of the influence on the concealed bracing concrete core building by different concealed bracing reinforcement ratio and axial compression ratio is made in this article. Comparing load-displacement curves and stiffness displacement angle curves of the 16 finite element models, obtaining the corresponding value of the feature point, ultimately the conclusion of the advantages and disadvantages which brought by reinforcement ratio and axial compression ratio are drawn.