【摘要】 过度抽取地下水造成的地面沉降正逐渐成为一种严重的地质灾害。在现有成果的基础上,设计、研制地面沉降室内试验装置,并改进试样的饱和方法。使用该装置模拟释水引起的地面沉降,从地面沉降对水位变化的响应和地面沉降过程中的孔隙水压力变化两方面研究地面沉降的滞后性。分析结果得出:(1)承压含水砂层和黏土层的变形均表现出滞后现象;(2)相同试验条件下,黏土层变形的滞后时间随着土层厚度的增大而增加。地面沉降试验完成后,分别从黏土层的底部和顶部取出试样进行室内常规压缩固结试验,试验结果表明:抽水引起的地面沉降在垂直层面方向上是不均匀的,距离抽水含水层越近的部分其压缩程度越大。更多还原

【Abstract】 Land subsidence caused by groundwater overpumping is becoming a serious geological disaster.Based on previous studies,testing device of land subsidence was manufactured and the saturation method of sample was improved.Land subsidence caused by water releasing was simulated by the use of this device.Hysteresis effect of land subsidence was studied on land subsidence response to changes of water level and pore water pressure in the process of land subsidence.The results show that:(1) The deformations of both confined aquifer and clay layer show lag phenomenon;(2) Under the same test conditions,the lag-time of deformation of clay layer was(going longer with the thickness of caly layer)in direct proportion to thickness of clay layer.When the test was completed,clay specimens were taken out from the bottom and top of clay layer respectively and measured by conventional consolidation test.The results indicate that the land subsidence caused by water releasing was not uniform in the vertical direction.The shorter the distance between the clay layer and the pumping aquifer is,the greater the degree of compression of the clay layer is.更多还原