煤层等软岩层地应力研究新方法及其应用

目前煤层等软岩层地应力研究方法匮乏,地应力测量难度很大,因此有关煤层垮塌失稳力学机理的研究还无法深入.针对这一现状,利用含煤层系地层中硬岩层的地应力实测结果,以组合弹簧模型为基础,计算出构造作用引起岩层水平方向的应变量,并以此作为整个含煤层系地层地应力有限元分析的边界条件,建立含煤岩层地应力有限元分析模型,将硬岩层的地应力实测、理论模型计算以及有限元数值模拟三者有机结合起来,反演得到煤层等软岩层的地应力状态,从而建立起一套煤层等软岩层地应力研究的新方法.

A new Method for researching the earth stress of soft rock strata such as coal-bearing strata and its application

There is not a good method for researching the earth stress in the soft rock such as coal-bearing formation.So it is difficult to study the sloughing mechanism of coal bed.In view of the present situation,the horizontal strain magnitude of the rock strata caused by tectonic action can be calculated based on the earth stress measurement in the hard rock in the coal bed and the combined spring model.Taking the horizontal strain magnitude as the boundary condition in the finite element analysis of the earth stress,a finite element model for calculating the earth stress field of coal-bearing formation is set up.Combining the earth stress measurement in hard rock,theoretical model calculation and finite element numerical simulation,a new method for researching the earth stress in the soft rock such as coal-bearing formation is developed.The method can be effectively used for the determination of the earth stress state in coal bed and other soft rockes.Some application cases show that this method is feasible,and it can be applied in oilfield development and other underground works.