超大截面钢管混凝土柱分配梁构造节点下轴压荷载传递试验研究

发布时间：2018-04-09 14:01

本文选题：超大截面矩形钢管混凝土柱　切入点：压力分配梁　出处：《土木工程学报》2014年10期

【摘要】：为保证超大截面矩形钢管混凝土柱中钢管和混凝土的共同工作性能,在前期研究的基础上对荷载作用于管壁的超大截面矩形钢管混凝土柱1∶5缩尺模型进行轴压承载力试验研究,试件在节点核心区采用压力分配梁构造参与荷载传递,试验参数考虑钢管宽厚比、压力分配梁刚度。结果表明:所有试件试验承载力均基本达到90%以上名义承载力(Nu=fyAs+fckAc),表明采用压力分配梁构造具有良好的荷载传递性能;竖向荷载通过界面黏结强度及滑动摩擦力传递至核心混凝土非常有限,主要通过分配梁传递至核心混凝土;分配梁刚度的变化会导致试件破坏模态的转变,分配梁H200×100×10×10试件为混凝土压溃破坏,分配梁H130×70×6×6试件为钢梁剪切撕裂破坏,且分配梁刚度相对较小时尽管试验承载力达不到名义承载力,但具有更好的延性性能;采用分配梁构造无法保证钢-混凝土之间变形协调,主要原因是分配梁加载过程中产生较大塑性变形,但试验荷载-位移曲线及破坏模态表明分配梁与钢梁周围混凝土的组合作用能够保证竖向荷载直接有效地传递至核心混凝土。
[Abstract]:In order to ensure the common performance of steel tube and concrete in the concrete filled rectangular steel tube column with super large section,On the basis of the previous research, the axial bearing capacity of the super-large section rectangular concrete-filled steel tubular column at 1:5 scale model acting on the pipe wall is studied. The specimen takes part in the load transfer by using the structure of the pressure distribution beam in the core area of the joint.The test parameters consider the ratio of width to thickness of steel pipe and the stiffness of pressure distribution beam.The results show that the bearing capacity of all specimens is above 90%, which indicates that the structure of pressure distribution beam has good load transfer performance.The vertical load is transmitted to the core concrete through interfacial bonding strength and sliding friction force, mainly through the distribution beam to the core concrete, and the change of the stiffness of the distribution beam will lead to the change of the failure mode of the specimen.The distribution beam H200 脳 100 脳 10 脳 10 is concrete crushing failure, and the distribution beam H130 脳 70 脳 6 脳 6 is shear tearing failure of steel beam, and the stiffness of the distribution beam is relatively small, although the experimental bearing capacity is not up to nominal bearing capacity, it has better ductility.The deformation coordination between steel and concrete can not be guaranteed by the construction of distribution beam, which is mainly due to the large plastic deformation of the distribution beam during loading.However, the experimental load-displacement curves and failure modes show that the combined action of the distribution beam and the concrete around the steel beam can ensure the vertical load to be transferred directly and effectively to the core concrete.
【作者单位】：同济大学;悉地国际(深圳)设计顾问有限公司;
【基金】：国家自然科学基金(51208375)
【分类号】：TU398.9

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