1引言在铁路框架桥施工中,当墙身厚度较大、框架长度较长时,墙身经常出现裂缝,它属于非荷载(暨结构尚未使用)引起的砼结构开裂。砼产生裂缝的原因复杂,有原材料、设计、施工、管理以及气温等多方面的因素,而且往往是多种因素的综合体现。 1 Introduction In the construction of railway frame bridge, when the wall thickness is larger and the frame length is longer, the wall often cracks, which belongs to the cracking of concrete structure caused by non-load (the cum structure has not been used). The causes of cracks in concrete are complex, with many factors such as raw materials, design, construction, management and temperature, and are often the result of a combination of factors.