在铁路路基沉降变形评估的基础上合理缩小铁路保护带宽度是关系湖北云应盐穴储气库项目是否可行的关键问题。盐穴储气库地表沉降变形的主要诱因是运营期间地下腔体体积的蠕变收缩。从经典唯像学的角度出发,将盐穴储气库地表沉降剖面曲线拟合为Gauss函数,假设地表沉降盆地体积与盐腔蠕变收缩体积有着近似正比的关系,引入体积传递系数a和影响角γ这2个关键参数,得到一定体积收缩条件下的单腔储库地表沉降公式,并将其应用在湖北云应拟建盐穴储气库地表沉降预测的评估研究中,利用沉降叠加的方式获得运营期间储气库群地表沉降发展趋势。根据储气库群地表沉降评估结果,按照不同的路基沉降变形标准给出缩小铁路保护带宽度的建议和结论,并提出控制盐穴储气库群地表沉降和减小路基沉降影响的若干措施。
It is a key problem for reducing the width of railway safety belt reasonably according to the evaluation result of railway roadbed subsidence and deformation, which determines the feasibility of Hubei Yunying salt cavern gas storage group. The creep contraction of salt cavern volume during operation period is the main cause of ground subsidence. Based on the hypothesis that the subsidence basin volume approximately has a relation of direct ratio with the creep contraction volume, the ground subsidence curve could be fitted as a Gauss function. Two key parameters of volume transfer coefficient and impact angle were introduced; and the formula for ground subsidence above a single cavern was deduced under condition of a certain volume shrinkage. The formula was used in the ground subsidence prediction of planned Hubei Yunying salt cavern storage. Finally, the ground subsidence above the salt cavern gas storage group was forecasted by superposition method. To solve the conflict of railway safety belt and planned salt cavern site, according to different roadbed deformation standards and salt cavern gas storage group ground subsidence above prediction results, the suggestion of reducing width of railway safety belt is given, as well as the control method to reduce the ground subsidence above salt cavern gas storage group and the roadbed subsidence effect.