Land subsidence and cracking due to groundwater depletion.
Land subsidence and cracking due to groundwater depletion.
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DOI：
10.1111/j.1745-6584.1977.tb03180.x
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发表时间：
1977-01-01
期刊：
影响因子：
2.6
通讯作者：
Bouwer, H.
中科院分区：
文献类型：
--
作者：
Bouwer, H.
由于地下水超采引起的地表沉降是由松散含水层和其他地下物质的粒间压力增加引起的。对于无承压含水层，这种增加是由于由于地下水位下降而脱水的区域中固体颗粒的浮力丧失的结果。对于承压含水层，晶间压力的增加是由于上围水层底部向上的水力压力减少造成的，这是由于测压面下降所致。粒间压力增加的层的压缩可以用弹性或对数理论来计算。样本计算得出的沉降率与观测结果一致，即每10米地下水位下降约5至50厘米。地下水枯竭也会产生地表裂缝，特别是在沿边缘或沉降盆地其他部分的基岩深度不连续之上。基于旋转板理论的计算表明，这些裂缝的初始表面宽度约为1 cm，与现场观测结果一致。
Subsidence of the land surface due to groundwater overdraft is caused by an increase in the intergranular pressure in unconsolidated aquifers and other underground materials. For unconfined aquifers, this increase is the result of a loss of bouyancy of solid particles in the zone dewatered by the falling water table. For confined aquifers, increases in intergranular pressure are caused by decreases in the upward hydraulic pressure against the bottom of the upper confining layer, due to a drop in piezometric surface. Compression of layers in which the intergranular pressure is increased can be calculated with elastic or logarithmic theory. Sample calculations yield rates of subsidence that agree with those observed, i.e., about 5 to 50 cm per 10-m drop in groundwater level. Groundwater depletion can also produce surface cracks, particularly above discontinuities in bedrock depth along the periphery or in other parts of subsiding basins. Calculations based on the rotating-slab theory show that the initial surface width of such cracks is about 1 cm which agrees with field observations.