大直径预应力混凝土煤仓在内压荷载下的受力分析

Analysis in wall stress of large-diameter prestressed concrete coal silo under internal pressure

基于圆柱壳力学的有矩理论,考虑长壳底部约束影响的局部化特征,将预应力对大直径预应力混凝土煤仓(PCCS)的作用等效为仓壁的均布内压,推导了同时考虑预应力效应与仓底边缘效应的径向位移与内力计算公式。算例理论分析与有限元计算结果的对比表明:两者具有良好的一致性;在距底部2.5(Rt)^(1/2)的仓壁范围内,传统设计方法的内力计算结果与本文公式及有限元分析差别较大,因此须在精确得到此区域内力的基础上对大直径PCCS进行精细化设计。

The formulas for the radial displacement and inner forces of large-diameter PCCS （ prestressed concrete coal silo） were derived, based on the mechanics of cylindrical shell and considering the boundary condition at the bottom. The prestressed action was equivalent as the internal pressure. The two reauhs calculated by the formulas and the FEA have good agreement. The results show that the results within 2. 5√Rtfrom the bottom may be remarkably different between the formula and the traditional design theory, which indicates that the precise design is necessary for this region.