中文摘要：

针对南水北调工程中预应力钢筒混凝土（PCCP）管芯混凝土预存裂缝问题，通过对原型管道的抗裂外压承载力试验，探讨了预存管芯外壁纵向裂缝对承载力的影响，分析了混凝土管的受力特性。试验结果表明，PCCP在抗裂外压检验荷载下，其破坏主要发生在管顶、管底内侧管芯混凝土和管腰外侧砂浆保护层的受拉破坏。基于ABAQUS有限元分析，选用混凝土塑性损伤模型，对PCCP抗裂外压试验进行结构数值模拟，数值计算与试验结果一致。计算结果表明，管芯混凝土预存裂缝对PCCP抗裂外压极限荷载影响不大，但在外载作用下，预存裂缝会对混凝土、砂浆保护层出现应力集中现象，从而导致裂缝的发生与扩展。

英文摘要：

The effect of longitudinal cracks in the outer wall of prestressed concrete cylinder pipe （PCCP） in the South-to-North Water Transfer Project is investigated by external bearing capacity tests in prototype. The experiment results indicate that tension damage of PCCP is distributed in the roof and bottom of inner core pipe and in the middle of lateral pipe. Based on ABAQUS finite element analysis, selecting the damaged plasticity model for concrere, the structure performance of PCCP is analyzed by means of numerical, simulation. The numerical calculation result is consistent with the experiment result. The numerical results show that the anti-crack external pressure ultimate load is a little effected by the crack in the core concrete of PCCP. However, the stress of concrete and mortar is concentrated around the crack and the damage of concrete will happen under the external load.