不同洞距下内衬式高压储气库热-力特性分析

Thermal and mechanical characteristics analysis of lined high pressure gas storage with different cavern spacing

以安徽某深部硬石膏矿体建造大规模内衬岩洞式储气库为研究背景,采用ABAQUS有限元软件的热-力耦合分析方法,研究深埋洞室不同洞距下多循环充采气过程中关键结构层温度、变形、应力的分布及变化过程,探究不同洞距时围岩塑性区分布规律以及地表变形变化过程。结果表明:增大洞距对主要结构层的温度基本没有影响;洞距小于2倍洞径时,改变洞距对关键结构层的应力和变形、地表位移、混凝土衬砌的拉应力分布和大小以及围岩塑性区的分布有较为明显的影响,储气库间的相互作用较为显著;当洞距增大到2倍洞径后,储气库间的相互作用已经不再明显,此时增大洞距对储气库的稳定性没有明显的增强效果。

The research background was the construction of large-scale lined cavern gas storage for a deep anhydrite ore body in Anhui province,the thermal-mechanical coupling analysis method based on ABAQUS finite element software was used,established numerical model under the gravity stress field,the deep cavity multi cycle under different cavern spacing was apart from the temperature,the gas extraction in the process of filling the key stratum structure deformation,stress distribution and the change process.The distribution law of surrounding rock plastic zone and the change process of surface deformation under different cavern spacing were investigated.The results showed that the temperature of the main structural layers was not affected by increasing the cavern spacing.When the cavern spacing was less than 2 times the hole diameter,changing the cavern spacing had obvious effects on the stress and deformation of key structural layers,surface displacement,tensile stress distribution and size of concrete lining,and plastic zone distribution of surrounding rock,and the interaction between gas storage was more significant.When the cavern spacing increased to 2 times the cavern diameter,the interaction between gas storage was no longer obvious,and the increase of cavern spacing had no obvious effect on the stability of gas storage.