钢-混凝土组合梁的温度应力计算

Calculation of Temperature Stress of Steel-concrete Composite Beam

重点考察了钢-混凝土组合梁在任意温度分布作用下应力的计算方法。首先在指出传统温度应力计算方法不足的同时,根据结合面变形协调条件和曲率相同假设,推导出不考虑滑移时,矩形温差作用下组合梁应力的计算方法;接着采用有限元理论,推导出任意温度分布下,组合梁温度应力的计算方法,并分别给出温度梯度和矩形温差作用下的温度应力计算公式;最后以某一钢-混凝土组合梁为例,将各方法的计算结果进行了比较。结果表明:对于适用于计算矩形温差的基于曲率的方法,计算矩形温差作用下的应力,与通用有限元软件模拟结果相吻合;对于适用于计算任意温度分布形式的有限元方法,计算温度梯度分布下的应力,与通用有限元软件模拟结果吻合较好。

The calculation method of temperature stress of steel-concrete composite beam under arbitrary temperature distribution was discussed.First,the disadvantage of traditional method for calculating temperature stress was pointed out.A method for calculating stress under rectangle temperature difference without considering the effect of the slip between steel beam and concrete deck was derived based on the deformation compatibility condition of the joint surface and the assumption of identical curvature.Second,based on the finite element theory,another calculation method was derived,and the formulas for calculating the temperature stress under temperature gradient and rectangle temperature difference were developed respectively.Finally,taken a steel-concrete composite beam for example,the calculation results from each method were compared.It shows that（1） for calculating the stress under rectangle temperature difference,the result using the method suitable for calculating rectangle temperature difference based on curvature agrees well with that using finite element analysis software;（2） for calculating the stress under temperature gradient,the result using the method suitable for calculating any temperature distribution based on the finite element method agrees well with that using finite element analysis software.