海岛地下水封洞库围岩稳定性及水封可靠性研究

为提高我国的石油储备量及海岛资源利用率,在海岛环境建造地下水封油库成为了一种新的思路。海岛环境相比于内陆具有更好的水力条件,且可作为港口,便于油品运输。以某海岛地下水封油库为依托,基于流固耦合理论,采用有限元数值模拟方法对海岛环境建造地下水封洞库的围岩稳定性和水封可靠性进行研究。结果表明:在海岛环境建造地下水封洞库围岩的应力和位移均较小,可以满足围岩稳定性要求;在不设置水幕系统情况下,开挖地下洞库会在洞库上方形成明显的降落漏斗,部分洞库顶部甚至发生疏干现象,无法满足水封可靠性要求;在设置水幕系统后,地下洞库上方可形成较大厚度的地下水覆盖层,可以满足水封可靠性要求。该成果对在海岛环境下建造地下水封洞库的研究具有借鉴意义。

Study on Surrounding Rock Stability and Water-sealed Reliability of Underground Crude Oil Storage Cavern in Island

In order to improve the quantity of oil storage and the utilization rate of island resources in China, it is a new idea to build underground water-sealed oil storage cavern in island environment. Compared with inland, island environment has better hydraulic conditions and can be used as a port for oil transportation. In this paper, based on an island underground water sealed oil depot, the surrounding rock stability and the water-sealed reliability were studied by using finite element numerical simulation method considering the flow-solid coupling theory. The results show that: the stress and strain values of surrounding rocks are small in island environment, which can meet the stability requirements of surrounding rock. In the case of without water curtain system, the excavation of the underground caverns will form obvious depression cones above the caverns, and some of the caverns will even dewatering aquifer, which cannot meet the requirements of water-sealed reliability. Under the influence of water curtain system, a thicker groundwater cover can be formed above the underground cavern, and underground caverns can meet the requirement of water-sealed reliability. The results provide theoretical basis for the research of the construction of the underground water-sealed oil storage cavern under island environment.