内置钢箱-混凝土连续组合梁受力性能试验

Experimental research on mechanical behavior of continuous encased steel box concrete beam

为研究超静定内置钢箱-混凝土组合梁的塑性设计方法,进行了4根两跨内置钢箱-混凝土连续组合梁试验,获得了试验梁裂缝分布与开展、变形发展、破坏特征及塑性内力重分布等方面的试验结果.通过分析,给出了内置钢箱-混凝土连续组合梁等效塑性铰区长度计算公式,提出了以支座控制截面弯矩弹性计算值与组合梁正截面破坏时钢箱所承担弯矩之差为调幅对象、以相对塑性转角为自变量的弯矩调幅设计方法.

In order to investigate the plastic design method of indeterminate encased steel box concrete beam （ ESBCB）, 4 two - span continuous ESBCBs are tested, and then the distribution and growth of crack, deformation, failure characteristics and redistribution of plastic internal force are obtained. The calculation formula of the length of equivalent plastic hinge of ESBCBs is presented. A design method for moment modification is put forward, in which the object of moment modification is the difference between the elastic calculated moment of critical section at intermediate support and the moment subjected to the steel box when the composite beam reaching the limit state of bending capacity, and the variable is the relative plastic rotation.