论文部分内容阅读
层状盐岩界面的抗剪强度特性对储气库的稳定性和密闭性具有决定性影响。依托湖北应城盐矿地质和试验资料,讨论不同种类界面的强度特性,提出2种主要界面的抗剪强度模型,并给出破损机制分析。主要结论有:(1)层状盐岩大部分界面为化学沉积界面,因此为强界面,比如盐岩和泥质硬石膏的界面,少部分为机械沉积界面,因而为弱界面,例如泥岩和岩盐的界面,弱界面一般存在于不连续沉积的突变界面处;(2)提出渐变型界面和突变型界面2种不同剪切强度模型,渐变型界面近似于功能梯度材料,突变型界面可以近似作为盐岩和夹层的接触面;(3)渐变型界面可以较好地传递盐岩和夹层由于变形不协调产生的附加作用力,因而不容易产生破损,而突变型界面则不能。建立界面抗剪强度特性与其沉积地质特征之间的相关性,为盐穴油气储库的稳定性和密闭性研究提供重要的参考。
Shear strength characteristics of layered rock salt interface have a decisive influence on the stability and airtightness of gas storage. Based on the geological and experimental data of Yicheng Salt Mine in Hubei Province, the strength characteristics of different kinds of interface are discussed. The shear strength models of two main interfaces are proposed and the damage mechanism is analyzed. The main conclusions are as follows: (1) Most of the interface of layered rock salt is a chemical depositional interface, so it is a strong interface, such as the interface between salt rock and argillaceous anhydrite, and a few of them are mechanical depositional interfaces and thus weak interfaces such as mudstone and The interface between rock salt and weak interface generally exists in the discontinuous interface of discontinuous deposition. (2) Two different shear strength models are proposed for the gradient interface and the abrupt interface, the gradient interface is similar to the functionally graded interface, and the abrupt interface can be approximated As the contact surface of salt rock and interlayer; (3) Gradient interface can well transfer the salt rock and interlayer due to the additional force generated by the uncoordinated deformation, which is not easy to produce damage, but the mutant interface can not. Establishing the correlation between the interface shear strength characteristics and the sedimentary geology features provides an important reference for the study of the stability and tightness of the salt caverns reservoir.