定水头注水引起的含水层水平运动和应变

基于含水层固体颗粒与孔隙水不可压缩的假设 ,本文导出了单井注水情况下泰斯承压含水层水平运动速度与水头之间的基本关系式。然后利用注水井壁处的应力、应变边界条件 ,进一步导出了单井定水头注水引起的泰斯承压含水层水平运动速度、位移和应变解析表达式。该水平位移与应变由两部分组成 :一部分为由注水压力本身引起的经典弹性力学解项 ,它仅随半径而变化 ,与注水时间无关 ;另一部分为由地下水头变化引起的水动力学位移和应变解项。其中 ,含水层水动力学水平位移随时间加长呈指数增长特征 ,水动力学径向应变则表现为近井处拉张、远井处挤压的分区特征 ,且近井拉张区随时间加长逐渐向外扩展。单井注水含水层水动力学水平位移、应变解的导出 ,完善和发展了单孔内压经典弹性平面力学问题解

HORIZONTAL AQUIFER MOVEMENT AND STRAIN CAUSED BY WATER INJECTION OF FIXED HEAD

On the basis of hypothesis of solid grain and interstitial water uncompressible, we firstly establish a governing equation between horizontal aquifer movement velocity and hydraulic head for axissymmetric water injection in Theis Thiem confined system. By applying the stress and strain boundary conditions at the injection well, we further derive the analytical expressions of the horizontal aquifer movement velocity, displacement and strains caused by water injection in a single well. The displacement and strains derived are composed of two parts: part one, the classical elastic solution caused by water pressure; and part two, the hydro dynamic solutions caused by change in hydraulic head, where the hydro dynamic horizontal displacement increases exponentially along with time, the hydro dynamic radius strain can be divided into inner tension zone and outer compression zone, and the inner tension zone gradually expands along with time. The obtaining of hydro dynamic solutions of horizontal aquifer displacement and strains caused by water injection in a single well, can be regarded as an improvement for the classical plain problem of inner pressure in single hole.