混凝土温度自应力数值计算方法

The Program Analysis of Self-equilibrating Thermal Stresses

混凝土的温度自应力广泛存在于混凝土桥梁中,关于截面温度自应力的计算,铁路规范虽给出相关算法,但操作性较差。为了更准确且高效地计算温度自应力,基于平截面假定,以温度自应力不产生内力为基本原则,推导相关计算公式,并编写对应计算程序。分别对计算公式进行自校,并与三维有限元法计算结果相比较,对比表明,两者计算结果基本相同。

With the increasing of long span prestressed concrete box girder bridge,especially in the statically indeterminate continuous girder bridge system,the temperature stress can reach or exceed the live load stress,which has been one of the main causes of cracks in prestressed concrete bridges.On the calculation of section temperature stress,although the relevant specifications are given in railway codes,it is difficult to use.Therefore,in order to calculate the temperature stress more accurately and efficiently,the relevant calculation formula is derived based on the assumption of plane section and the basic principle that temperature self-stress does not generate internal force,and the corresponding software programis written.At last,according to the characteristics of temperature stress,a self-calibration of the programis made.The calculated results of the program and the results of the three dimensional finite element method are compared,and the results show that the calculation results of both are basically same.