Formwork breakup during piers construction may occur when lateral pressure of fresh concrete exceeds allow able bearing capacity of form work,rod and bolts. Failure of form work or connection results in collapse of entire formwork system and fresh concrete. The primary cause of formwork breakup is that the height of once casting fresh concrete is higher than the allow able value,and the secondary causes are the defects of the structure and installation of formwork system. Thus,strength and stability shall be checked to avoid breakup,and specific construction plan shall be established. The maximum height shall not exceed the limit height of the formwork system and be within 9 m. Inspection shall be performed as the formwork is delivered to the site. Installation shall be firm and reliable.%桥梁墩身施工中新浇筑混凝土侧向压力超过模板、拉杆、连接螺栓等的容许承载能力时,会导致局部破坏从而引发整个模板支撑系统及新浇筑混凝土坍塌.混凝土一次浇筑高度超过模板限定高度是桥梁模板爆裂的主要原因,模板结构及安装不规范也是模板爆裂发生的原因.预防墩身施工模板爆裂须做到对模板强度和稳定性进行检算;须有施工专项方案;一次浇筑最大高度不得超过模板限定高度且不超过9m;墩身模板运抵现场后,须进行验收;模板安装须稳固.
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