界面变形对钢-混凝土组合梁挠度影响的分析

The impact of interface deformation to deflection of steel-concrete composite beam

为深入研究界面对钢-混凝土组合梁力学行为的影响,在以往Goodman弹性夹层假设基础上,引入界面柔度系数,考虑了界面变形引起的整体变形效应。在界面相对滑移本构方程基础上,通过组合梁力平衡方程得到了钢-混凝土组合简支梁在均布荷载作用下的挠度变形理论计算公式。算例结果表明,该计算公式能准确反映钢-混凝土组合梁变形,为钢-混凝土组合梁在正常使用极限状态下的挠度计算提供了一种新的可靠计算方法。结果还表明,界面刚度对整体变形影响较大,忽略界面变形的效应,组合梁挠度可能被低估。

Aim to study the influence of interface slip to the mechanical behavior of steel-concrete girders and analyzing the sliding effect caused by interface deformation, a new method is presented based on the assumption of Goodman elastic sandwich by introducing interface flexibility coefficient. The combination of beam force balance equation and interface relative slip constitutive equation,the theoretical calculation formula of deflection deformation and interface slip of steel-concrete composite beams under uniform load are derived. Numerical examples results showe that the theory is correct and accurate to solve the problem of the deformation of the steel- concrete composite beam. The new reliable calculation method for the deflection calculation of the steel-concrete composite beams under normal use limit state is presented. Further more,the interface rigidity is found to have significant influence on the overall deformation. The deflection of composite beam may be underestimated by ignoring the interface deformation.