预应力混凝土建筑施工事故案例分析

施工期间的预应力钢筋混凝土结构,是时变结构体系,除承受施工荷载外,还承受预应力等效荷载,因缺乏理论支持,其设计施工容易出现问题.本文介绍的某工程实例为预应力钢筋混凝土结构,且设计有跨后浇带与不跨后浇带两组预应力钢筋,施工期间后浇带两侧结构出现过大变形差,影响结构施工安全,通过将后浇带钢筋的约束作用简化为弹性支座,分析对象简化为弹性支座连续梁,并考虑施工荷载和等效预应力荷载,分析了该工程出现过大变形的原因,结合预应力筋锚固角度等参数分析,给出了留后浇带预应力钢筋混凝土结构设计施工的建议.

Accident Analysis of Prestressed Reinforced Concrete Structures During Construction

The prestressed reinforced concrete structure during construction is a time-dep endent structural system. The loads acting on the structure include con struction load and prestressed equivalent loads. Because of lacking of theory, t he errors usually appear in the design and construction of the structure. For ex ample, one real engineering is a prestressed reinforced concrete structure, and two sets of prestressed steel bar are designed, one comes through the strip of p ost pouring concrete and the other don't, moreover abnormal deformation is produ ced in construction of the structure. Therefore a continuum beam with elastic se at coming from the restrict of steel bar in a strip of post pouring concrete is proposed, considering the construction loads and prestressed equivalent loads, f urthermore causes of abnormal deformation are analyzed. The parameters of ancho r angle of prestressed steel bar and stiffness of elastic seat, etc. are studie d, then the suggestions for design and construction of prestressed concrete str uctures with a strip of post pouring concrete are given.