巨型钢管混凝土柱共同工作性能数值分析

Numerical Simulation of Detailing Requirements to Guarantee Cooperation Between Steel Tube and Concrete in Concrete filled Steel Tubular Columns with Large Rectangular Section

摘要:

为研究超高层建筑结构中大型转换梁(或转换桁架)与巨型钢管混凝土柱连接处超大截面矩形钢管混凝土柱中钢管与核心混凝土的共同工作性能，针对提出的节点内直接设置分配梁的构造，采用ABAQUS软件对3种不同构造措施的4个超大截面矩形钢管混凝土柱1∶5缩尺模型的轴压试件进行了非线性有限元分析，结果表明，有限元分析得到的轴压荷载位移曲线、混凝土工作承担系数曲线和破坏模态均与试验吻合良好，验证了有限元模型的有效性.在此基础上通过有限元分析考察了分配梁刚度和管壁宽厚比对仅设置分配梁和分配梁加环板2种构造的超大截面矩形钢管混凝土柱钢混凝土共同工作性能的影响，分析表明，管壁宽厚比对超大截面矩形钢管混凝土柱钢混凝土共同工作性能影响较小；增大分配梁的刚度可以较大地改善钢混凝土的共同工作性能.

Abstract:

In order to investigate the cooperation property between steel tube and core concrete at the connections between giant transfer beams(or trusses) and mega concrete filled steel tube columns in the extra high buildings, 4 scaled specimens (1∶5) for large rectangular section concrete filled steel tubular (LRCFT) columns with 3 types of detailing requirements under compression load, which was applied directly on the steel tube, were analyzed with ABAQUS. The finite element models adopted in this paper were verified by comparing with the axial compression load vertical displacement curves, percentage curves of the load carried by core concrete ,and the failure modes between FEM’s and experimental results. Based on such verified models, two impact factors, i.e., the width to thickness ratio of the steel tube and the stiffness of distributive beams, were investigated to understand the influence on cooperating behavior between steel tube and core concrete in the LRCFT columns with distributive beams and both distributive beams and inner diaphragms simultaneously. It is shown that the width to thickness ratio of the steel tube have small effect on the cooperation property between steel tube and concrete in the LRCFT columns, however, the cooperation would be improved with the increasing of the distributive beams stiffness.