PC钢筋在高压蒸汽养护过程中的失效分析

通常认为ＰＣ（ＰｒｅｓｔｒｅｓｅｄＣｏｎｃｒｅｔｅ）钢筋在高压蒸汽养护过程的断裂原因是应力腐蚀断裂，而且腐蚀环境起着十分重要的作用。通过对高压蒸汽养护断口及相关的成份分析、组织分析，认为造成ＰＣ钢筋高压蒸汽养护断裂的主要原因是成份组织不均匀，使内应力过大，钢筋在预张应力条件下局部区域过载。氢脆也是一个造成高压蒸汽养护中断裂的重要因素，而相比之下高温、高压、腐蚀环境，对断裂的影响较小。

FAILURE ANALYSIS OF PC REINFORCED STEEL BAR IN HIGH PRESSURE STEAM KEEPING

The breaking reason of PC(Prestressed Concrete) reinforced steel bar in high pressure steam keeping usually was considered as stress corrosion cracking, and the corrosive environment has very important role. This paper had studied its fracture surface, composition and structure, the result is shown that the main reason of fracture is excessive internal stress caused by inhomogeneous composition and structure, which result in part area excessive loading of the steel rod in pre-tensioning, Hydrogen embrittlemtnt is an important reason too, high temperature, high pressure and corrosive environment have less influence as compared to above two reasons.