【摘要】 为了对深部盐岩储气库建腔进行可行性分析,结合金坛盐岩矿区地层情况,采用三维快速拉格朗日方法对盐岩地层沉积过程的自重应力分布进行了模拟计算,分析含夹层盐岩地层沉积过程自重地应力场的时空演化规律,得到了含夹层深部地层自重地应力垂直应力和侧压力系数的确定方法。结果表明,静力情况下,初始垂直地应力vσ、水平地应力hσ与埋深呈良好的线性关系,侧压力系数与半无限空间弹性理论值大体一致;蠕变作用下,岩层水平地应力不断增大直至与垂直地应力相等,最终使得岩层433.2 m以下处于静水压力状态,侧压系数变为1。总结金坛盐岩层初始地应力场分布规律可知,岩层分层面和夹层赋存的位置水平地应力会产生大幅突变,在储气库建腔设计及施工中应予以高度的重视。更多还原

【Abstract】 To study the feasibility of building gas storage cavern in deep rock salt and based on the actual stratum situation of salt rock mining field in Jintan,the sedimentation progress of salt rock stratum under the action of gravity was simulated by the three-dimensional finite-volume method,and then the time-space evolvement rule of gravity induced in-situ ground stress was analyzed. The calculation method of vertical pressure component of in-situ ground stress and the coefficient of horizontal pressure were proposed.It was shown that σv and σhlinearly increased with the depth in static situation,and the coefficients of horizontal pressure quite matched the elastic theoretical solution in halt infinite space,that the horizontal pressure component gradually increased until equal to the vertical component under the action of creep,and the rock stratum under 443.2 m was under hydrostatic pressure,accordingly,the coefficient of horizontal pressure became 1.In conclusion,serious attention should be paid to the construction of gas storage cavern,for there are horizontal groumd stress multations on the interface of rock stratum as well as in the mudstone inter-layers.更多还原