摘要
进行了主管内壁设置栓钉的钢管混凝土K形相贯节点(内栓钉节点)受力行为试验,同时进行了无内栓钉节点的对比试验。试验时在主管上施加压力,在两根支管上分别施加等量同步的压力和拉力。试验结果表明,该文节点的破坏为受压支管屈曲,荷载-受压支管变形曲线(N-S曲线)可分为弹性段和弹塑性段。无论有无内栓钉,主管焊接区域的应变都大于其他区域,它与荷载的关系曲线可分为弹性段和弹塑性段,而其余区域钢管均处于弹性状态。内栓钉不会改变主管钢管应变的分布规律,但是内栓钉的设置会减小主管钢管应变,表明内栓钉能将外力从钢管传递到管内混凝土,并且对应变集中的部位效果更显著。在主管轴向,应变主要集中在距离节点中心截面两侧各约2.7倍支管直径范围内;在主管环向,应变主要集中在圆心角-60°~60°区间。建议将此轴向与环向范围的应变集中区作为内栓钉的主要布设区域,区域外可以少布设或不布设。
The behaviors of Concrete-filled steel tubular （CFST） directly-welded K-Joints with studs on the inner wall of the main steel tube （inner stud） were tested, as well as a specimen without stud for comparison. During the test, the main tube was under axial pressure, while the two web members were equivalently and simultaneously under a pressure and a tension, respectively. The results show that for the buckling failure of web member, the load-displacement curve of compressive web member consists of a linear elastic stage and an elastic-plasic stage. With or without studs, the strains of the main tube in welding area are larger than those in other areas, whose load-strain curves include linear elastic stage and elastic-plasic stage, while the strains in the other areas are in elastic state. The stain distribution of stud does not change, but the stress magnitude is reduced, indicating that the studs are able to transfer force from steel tube to core concrete, especially at the strain concentration area. In the axial direction of main tube, strain concentration are observed at the two sides of the center section of joint, with a range of 2.7 times of the side tube diameter. In the circular direction, strains mainly concentrate in an area between directions -60° and 60°. It is suggested that the inner studs should be arranged mainly on these longitudinal and transverse areas, and sparsely or not arranged outside.
出处
《工程力学》
EI
CSCD
北大核心
2017年第9期150-157,共8页
Engineering Mechanics
基金
国家自然科学基金项目(51178118)
关键词
钢管混凝土
相贯节点
内栓钉
应变集中系数
布设范围
concrete-filled steel tube
tubular joint
inner stud
strain concentration factor
layout area
