降雨冲刷护管截水墙安全性模糊综合评判研究

Study on Safety of Pipe-Protection Cutoff Wall under Rainfall Erosion Effect Based on Fuzzy Comprehensive Judgment

截水墙是一种有效的油气管道水工保护结构,其受降雨冲刷毁坏将对油气管道安全稳定产生较大影响。根据西气东输沿线护管截水挡墙结构形式及其受降雨冲刷作用毁坏特征,综合考虑截水挡墙5种可能失效模式,利用模糊数学理论,建立了降雨冲刷护管截水挡墙安全稳定分析的变权模糊综合评判模型,结合工程实例验证了评判模型的可靠性,并对不同降雨强度下截水墙的安全性进行了分析。研究表明:降雨对截水墙的冲刷作用随着降雨强度的增加而增大,相应的安全性呈下降趋势,并且在一定的降雨强度范围内,截水墙的安全系数关于降雨强度呈二次函数关系;文中研究方法及结果对类似油气管道防护结构稳定安全性评判均有一定的参考价值。

Cut-off wall is an effective hydraulic structure to protect oil-gas pipeline, and would have a great impact on the safety and stability of oil-gas pipeline if it would be destroyed by rainfall erosion. Based on the structural styles and rainfall-caused damage characteristics of cut-off walls along the West-East pipe line in China, considering five possible failure modes of cutoff walls, using the theory of fuzzy mathematics, a weight-variation fuzzy comprehensive judgment model of cutoff walls＇ safety under rainfall erosion effect had been established. Combined with engineering examples to verify the reliability of the judgment model, the safety of the cutoff wall under different rainfall intensity had been analyzed. Studies have shown that the rainfall erosion effeet of the cutoff wall increased with the elevated rainfall intensity, on the contrary, the corresponding safety is on the decline, and the safety factor of the eutoff wall is in a quadratic function with rainfall intensity within a eertain range of rainfall intensity ; The methods and results of the research have a certain reference value to the structural stability and safety judgment of similar oil-gas pipeline protection engineering.