对预应力钢筒混凝土管(PCCP)蒸养制度的分析

Analysis of System for Steam Curing on PCCP

蒸养是继搅拌和振捣后影响水泥制品混凝土质量的关键环节,蒸汽养护在促进混凝土结构形成过程中,也对混凝土结构产生一定破坏作用,但合理的蒸养制度可以将此破坏作用减至最小。为此AWWAC301对PCCP蒸养作出了一些限制性规定。本文从养护工艺原理及混凝土物理化学变化过程入手,对引黄工程PCCP养护制度的建立进行了分析,经实践证明该养护制度是合理可行的。

Following the mixing and the vibrating,the steam curring became a key lin k influencing the quality of concrete product.The steam curing p romotes the structural formation of concrete,while it would causes a certain destructive effect on the concrete d uring the promoting process mention ed above.However,a rational regula tion on the steam curing may be able to minimize t he destructive effect .For exmple ,A WWAC301has laid down some peremptory regulations for the steam curing.In this paper,the analysis of setting up a system for steam curin g on PCCP,which had been used in Wanjiazh ai YRDP(Yellow River Diversion Project)was done ,starting with the principle in the curing technology a nd with the processes of physico -chemistry change of the concrete.It is p roved in practice that the system for steam cu ring on PCCP set up by Wanjiazhai YRDP is both rational and available·The cracks which are due to the steam curing have not yet been found in about 8000(one length is 5meters long)lengths of the PCCP producd by Wanjiazhai YRDP.