间接作用引起的墩身裂缝有限元分析

Finite Element Analysis of Pier Shaft Cracks Induced by Indirect Action

钢筋混凝土结构在施工或使用期间出现超过规范允许宽度的裂缝是一个常见问题。结合某铁路桥施工期间钢筋混凝土墩身开裂现象,通过理论与有限元仿真相结合的方法,对裂缝的出现原因及发展过程进行了分析。结果证实墩身裂缝是由温度、收缩等间接作用引起的,并在此基础上提出了有效控制裂缝宽度的方法。

It is quite a common problem that cracks with width greater than the allowable values in the specifications can occur in the reinforced concrete structure at both the construction and service stages. With reference to the cracks occurring in the reinforced concrete pier shafts of a railway bridge during construction, the causes leading to the cracks and propagation process of the cracks are analyzed by means of theoretic calculation and finite element simulation. The results of the calculation and simulation prove that the cracks in the pier shafts have been induced by the indirect action, such as that of the temperature stress and shrinking stress, and accordingly an effective method for control of the crack width is put forward.