围岩灌浆深度对水封石油洞库水封效果的影响

Effect of Rock Grouting Depth on Containment Property of Containment Oil Storage Cavern

地下水封石油洞库的水封措施直接影响洞库储油期渗流场及水封效果,围岩灌浆能显著改变地下洞库渗流场,进而影响洞库的水封效果.本文以我国首个大型地下水封石油洞库为例,研究在有无设置水幕、是否降雨的情况下围岩灌浆深度对洞库水封效果的影响.采用应力-渗流耦合理论,建立地下洞库有限元分析模型,利用大型商业软件ABAQUS设计多种计算方案进行数值模拟.通过模拟得到不同计算方案下孔隙水压力云图、洞库涌水量以及水封厚度数据.分析计算结果得出如下结论:全断面灌浆能有效防止储油期储油泄露;灌浆深度的增加能有效减少储油期洞库涌水量,提升洞库水封性能;灌浆深度为6 m时,该洞库水封厚度已足够,涌水量也较小.

The containment methods of underground containment oil storage cavern directly affect the seepage field and the containment effect during the oil storage period.Rock grouting around the cavern can significantly change the seepage field of the underground cavern,and then affect the containment effect of the cavern.Taking the first large-scale underground containment oil storage cavern in China as an example,the influence of surrounding rock grouting depth on the containment of the cavern is studied considering the effects of water curtain and rainfall.Based on the coupled stress-seepage theory,the finite element analysis model of underground cavern was established,and the simulation scenarios were designed by using large-scale commercial software ABAQUS.As a result,the pore water pressure contours and the groundwater inflow of the cave cavern and aquifer thickness above the cavern under different calculation schemes were obtained.The results show that full-face grouting can effectively prevent oil leakage during oil storage period,the increase of grouting depth can effectively reduce the groundwater inflow and improve the containment performance of the cavern.When the grouting depth is 6 m,the aquifer thickness above the cavern is sufficient and the groundwater inflow is small.