预应力混凝土安全壳模型施工期和后续使用性能分析

摘要

The nuclear containment is an essential barrier of the nuclear power plant,and its structural safety during construction and service life is notable.In this study,a 1 ∶ 3 scaled nuclear containment model was developed by using a commercial software ABAQUS based on the finite element method to investigate the performance of the containment subjected to gravity,concrete shrinkage,prestressing and internal design basis pressure.The numerical simulation results indicate that concrete shrinkage caused the restrained bottom mass concrete cracking.Cracks also took place around some containment holes after prestressing.Some cracks propagated under the internal design basis pressure,but other parts remained intact.The Von Mises stresses of most prestressed bars increased,but did not reach the yielding strength.The research results could provide reference for the design and construction of nuclear containments.%安全壳结构是核电站的一道重要安全屏障,其在施工期和后续使用期间的安全性备受关注.通过商业有限元软件ABAQUS建立安全壳结构模型(缩尺比例1∶3)研究在自重、混凝土收缩、预应力以及设计基准内压等荷载作用下安全壳的应力发展、变形情况以及开裂行为.计算结果表明,混凝土的收缩会使得受到约束的壳体底部大体积混凝土开裂.施加预应力后,孔洞周围混凝土会产生裂缝.在基准内压荷载作用下,部分裂缝会进一步扩展和延伸,但其他主体结构部分并未开裂.预应力钢筋的Von Mises应力有所增加,但并未达到钢材的屈服强度.研究结果可用于指导现有核电站的设计和施工.