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淮北某些矿区井筒变形、破坏严重，其主要诱发因素是下含水层水位下降而产生的附加应力。运用［２Ｄ－σ］软件进行了数值模拟认为：由于地下水位下降，地层与井筒发生相对位移而产生剪应力，其大小与水位降深和相对位移成正比；轴向应力随深度变化小，而随下含水层水位下降而增大；井壁破坏首先发生在其内缘，并逐渐向外扩展，破坏度沿深度方向增大；一含和下含同时有水位降时，轴向应力和剪应力的变化与单一含水层水位下降时相似，但轴向应力变化幅度明显增大，剪应力在上部含水层处增加。模拟计算分析结果与淮北地区井壁变形、破坏情况大体一致。
In some mining areas in Huaibei, the wellbore deforms and destroys seriously. The main inducing factor is the additional stress caused by the drop of the water level in the lower aquifer. The numerical simulation using [2D-σ] software shows that the shear stress is generated due to the descent of groundwater level and the relative displacement between the formation and the wellbore, and its magnitude is proportional to the depth and relative displacement of the water level. The axial stress changes little with depth Along with the lower aquifer water level increases, the damage to the well wall occurs firstly at its inner edge and gradually expands outwardly, and the damage degree increases along the depth direction. The change of stress is similar to that of a single aquifer, but the amplitude of axial stress increases obviously and the shear stress increases at the upper aquifer. The results of simulation calculation are consistent with those of wellbore deformation and damage in Huaibei area.