压气储能遂昌地下储气库结构应力变形特性数值研究

Numerical study on stress and deformation characteristics of structure of underground gas storage for CAES in Suichang

为了解压气储能地下储气库结构应力变形特性,以浙江遂昌拟建压气储能电站地下储气库为研究对象,采用热力耦合理论对运行条件下储气库的密封层、衬砌、围岩的应力变形特性及其变化过程进行了研究。研究表明:在循环充放气条件下,因储气库内压缩空气与密封层之间的热交换致使密封层温度出现较大幅度上升,而混凝土衬砌和围岩温度上升幅度较小。在距洞壁较近处,各结构层在高压作用下产生了较大的应力和位移,但随着与洞壁表面距离的增加,应力和位移逐渐减小。各结构层应力和变形均在允许范围内,储气库围岩稳定性良好。在循环压力的作用下,各结构层温度、位移及应力均呈现周期性的变化特征,且距洞壁越近,其变化幅度越大,而远离洞壁的围岩的温度及力学响应明显滞后。

In order to understand the stress and deformation characteristics of the structure of underground gas storage for compressed air energy storage(CAES),taking the underground gas storage of a planned CAES plant in Suichang,Zhejiang Province,as the research object,the stress and deformation characteristics and their variation process of sealing layer,lining and surrounding rock of gas storage under operating conditions were studied based on the thermodynamic coupling theory.The results show that the heat exchange between the compressed air in the gas storage and the sealing layer causes the temperature of the sealing layer to rise greatly,while the temperature of the concrete lining and surrounding rock rises slightly under the condition of circulating inflation and deflation.Where the structure is close to the tunnel wall,the stress and displacement of the structure under high pressure is larger,but the stress and displacement decreases gradually with the increase of the distance from the tunnel wall surface.The stress and deformation of each structural layer are in the allowable range and the stability of the surrounding rock of the gas storage is good.The temperature,displacement and stress of each structural layer all show the periodic changing characteristics under the action of circulating pressure,and the closer the distance to the tunnel wall,the greater the changing amplitude.While the temperature and mechanical response of the surrounding rock far away from the tunnel wall show obvious hysteresis.