考虑初始缝隙的埋藏式光面管临界外压经验公式

An empirical formula for critical external pressure of embedded penstocks without stiffener ring considering initial gap

为了避免水电站埋藏式压力钢管发生外压失稳问题,以埋藏式光面管为研究对象,首先对比分析了国内外主要临界外压经典理论与经验计算方法的不足,总结出临界外压的主要影响因素。根据一系列试验数据和原型资料进行回归分析,建立了考虑初始缝隙的临界外压经验公式。采用一系例工程实例对比验证了该公式的有效性,表明该公式可用于压力钢管临界外压的计算。

In order to avoid the buckling of embedded penstocks,taking the embedded penstock without stiffener ring as research object,we point out the defects of classical theoretical methods and empirical formulas at home and abroad,and summarize the main influential factors on critical external pressure（ CEP）. A CEP empirical formula that considers initial crevice is then proposed according to regression analysis of a series of test results and prototype data. The effectiveness of the presented method is proved by some engineering cases.