基于盐腔时效收敛特征的密集地下储气库群地面变形动态预测  

A dynamic prediction method for the ground surface deformation of concentrated storage groups based on time-dependent convergence characteristics of salt caverns

作　　者：陈雨[1,2] 李晓[1] 李守定[1] 

机构地区：[1]中国科学院地质与地球物理研究所·中国科学院工程地质力学重点实验室,北京市100029 [2]中国科学院研究生院,北京市100029

出　　处：《天然气工业》2012年第9期80-84,135,共5页Natural Gas Industry

基　　金：国家重点基础研究发展计划项目(973计划)(编号:2009CB724605;2010CB731501);国家自然科学基金资助项目(编号:41027001);中国科学院知识创新工程重要方向项目(编号:KZCX2-YW-JS102;YZ200912);中国地质调查局工作项目(编号:1212011220136)

摘　　要：盐岩具有显著的蠕变特性,盐腔在内外压力相互作用下表现出较明显的收缩性。为了掌握密集地下盐穴储气库群地面变形的动态发展规律,在综合考虑影响腔体收敛的多种时效因素(腔体水溶速率、体积收敛系数以及收敛传递率等)的基础上,对盐腔建腔期和运营期的腔体时效收敛函数进行了合理简化,基于腔体收敛传递假设,推导出腔体收敛传递函数,并结合地面沉降高斯分布规律和变形叠加原理,建立起一套较为完整的密集盐岩地下储气库群地面变形动态预测计算模型,提出了基于盐腔时效收敛特征的密集地下储气库群地面变形动态预测方法。实际应用结果表明:①地面沉降平均速率会随着时间的增加由大变小并逐渐趋于稳定;②地面计算点距离盐腔中心越近,初始沉降速率越大,其速率降低得越快。Because of the obvious creep characteristics of salt rocks,the salt cavern shows obvious contractibility under the interaction between internal and external pressures.To master the dynamic changing rules of the surface deformation of salt cavern gas storage groups,based on the consideration of several time-dependent factors affecting the cavern convergence,such as water dissolving rate,volume convergence coefficient,convergence transmissibility,etc.,this paper reasonably simplifies the cavern time-dependent convergence function during the cavern's construction and operation period,and deduces cavern convergence transfer function based on the cavern convergence transfer assumption.Combining with the Gaussian distribution curve and superposition theory,this paper establishes a set of dynamic prediction computational models for the ground surface deformation of concentrated underground gas storage groups based on salt caverns and puts forward a dynamic prediction method for the ground surface deformation of concentrated underground gas storage groups based on time-dependent convergence characteristics.The results show that the average subsidence rate will decrease as time goes and becomes increasingly stable.The nearer the calculation point is away from the salt cavern center,the larger the initial subsidence rate will be and the faster the rate will decrease.

关 键 词：密集 地下盐穴储气库群 地面变形 时效收敛变化 动态预测 收敛传递 水溶速率 

分 类 号：TE972.2[石油与天然气工程—石油机械设备]