中文摘要：

承压含水层减压降水实质上是一个卸荷过程，其上覆土层沉降可用基于弹性半无限空间Mindlin位移解的推导公式进行计算．分析表明：无限承压含水层非稳定渗流降水时间对土层沉降影响显著；由承压水减压降水引起的土层分层沉降随距地表距离的增加而增大，最大值位于承压含水层顶板处；影响上覆土层沉降的7个参数中，泊松比和承压含水层渗透系数的变化对土层沉降影响很小；上覆土层厚度、承压含水层厚度越大地表沉降值越小；上覆土层弹性模量较小时对地表沉降影响较大，随着弹性模量的增加，其对地表沉降的影响逐渐减弱；地表沉降随单井出水量、承压水水头降深的增大而增加且近似成线性关系；单井出水量、承压含水层厚度、承压水水头降深、上覆土层弹性模量不仅影响地表沉降值的大小，还会影响地表沉降的空间分布．

英文摘要：

Decompression and dewatering in confined aquifer is essentially an unloading process, and the overlaying soil settlement of confined aquifer can be calculated with the derive formulas based on the elastic half-space of Mindlin displacement solution. Analysis shows that influence of dewatering time of unsteady seepage in infinite confined aquifer on soil settlement is significant in comparison with the steady seepage. Soil settlement caused by decompression and dewatering of confined water increases with the increase of the distance to the ground and the maximum value emerges on the roof of the confined aquifer. Of the seven parameters affecting the ground settlement, Poisson ratio and the confined aquifer permeability coefficient affect the ground settlement little. Ground settlement decreases gradually with the increase of overlaying soil thickness and the confined aquifer thickness. The influence of elastic modulus on ground settlement, which is great when its value is small, gradually weakens with the increase of elastic modulus. Ground settlement increases with the increase of out-water volume of single well and water head drawdown, furthermore, a quasi linear relationship exists between them. The out-water volume of single well, the confined aquifer thickness, the water head drawdown and the elastic modulus of overlaying soil affect not only the value of ground settlement, but also the spatial distribution of ground settlement.