某核心筒连梁有楼面次梁搁置时的设计方法研究

Study on Design Method of a Core Tube Coupling Beam with Floor Secondary Beam

本文针对核心筒内部连梁有次梁搭接在上面的问题,提出三种针对连梁的抗震措施,分别为:在连梁内部设置交叉斜筋;增大连梁截面,使之成为变截面连梁;连梁内置型钢。本文主要研究思路为:首先,对结构进行小震下的振型反应谱分析及弹性时程分析,确保其符合“小震不坏”的抗震目标;其次,在中震不屈服分析下,建立上述三种措施下的模型,对比整体分析结果以及四层标准层配筋率,比选出内置型钢为最优方案;最后,对该方案进行大震下的动力弹塑性时程分析。结果表明,在中震和大震下,连梁内置型钢不仅能有效发挥耗能作用,而且没有发生剪切破坏,保护了搭接在上方的楼面次梁,为后续类似工程情况提供了参考。

Aiming at the problem that there is secondary beam overlapping on the coupling beam in the core tube,this paper puts forward three seismic measures for the coupling beam:setting cross diagonal reinforcement in the coupling beam,increasing the crosssection of the coupling beam to make it a variable cross-section coupling beam,and section steel built in the coupling beam.The main research ideas of this paper are as follows:firstly,the vibration mode response spectrum analysis and elastic time history analysis of the structure under small earthquakes are carried out to ensure that it meets the seismic goal of“small earthquakes are not bad”.Under the medium earthquake non yield analysis,the models under the above three measures are established,the overall analysis results and the reinforcement ratio of four standard layers are compared,and the built-in section steel is selected as the best scheme.Finally,the dynamic elastoplastic time history analysis of the scheme under large earthquakes is carried out.The results show that under moderate and large earthquakes,the built-in section steel in the coupling beam not only effectively plays the role of energy dissipation,but also does not have shear failure,which protects the floor secondary beam overlapped above.The paper provides a reference for similar projects in the future.