摘要
研究目的:地下水开采是引发地面沉降的的主要原因,且集中抽水引起的不均匀沉降会对高速铁路工程造成严重危害。因此,研究水井抽水引起地基变形过程,合理估算地基沉降范围,用以指导地面沉降区内的高速铁路选线及采取可靠的防治措施。研究结论:(1)基于离心模型试验结果,采用数值模拟方法模拟分析了不同深度条件下水井抽水引起地基沉降的规律和影响范围,模拟结果表明靠近抽水位置区域的地基变形大于远离水抽水位置区域,排水引起的地基沉降量与其不均匀程度随着排水次数和沉降的增大有逐渐减小的趋势;(2)不同深度抽水时引起地面沉降过程及影响范围有所不同,浅层抽水时不均匀沉降较为严重,影响范围较小,深层抽水时地基沉降较平缓,但影响范围较大;(3)承压水单井稳定流抽水引起的地基变形影响范围与含水层渗透系数负相关,与开采量正相关,若控制地下水开采量,其变形影响范围是可以控制的,一般不会超过1 000 m;(4)当高速铁路经过地面沉降易发区时,需采取绕避集中抽水区域、封井、禁采、限采及控制地下水开采量等多重措施;(5)该研究成果可指导高速铁路选线和铁路沿线地面沉降防治等领域。
Research purposes： Groundwater exploitation is the main cause of land subsidence, and the uneven settlement caused by centralized pumping is serious harm to high- speed railway projects. In this paper, the process of foundation deformation caused by the wells pumping is studied, and the extent of ground settlement is estimated reasonably, aiming to guide the railway line selection and take reliable preventive measures. Research conclusions： （ 1 ） Based on the results of centrifuge model tests, numerical simulation method was established accordingly to simulate the behavior and extension of ground settlement due to exploiting groundwater at different depth. The results show that the deformation of soils decreases with increasing distance from the well. The settlements and their difference due to pumping groundwater decrease with increasing number of exploiting cycles. （2） At the center district of land subsidence and vicinity of the well, the asymmetry subsidence is more serious with exploiting groundwater at a shallow depth, and its extent is narrower than that exploiting groundwater more deeply. （3）The influence extent of foundation deformation caused by steady flow pumping of the single well in confined water is negatively related to the permeability coefficient and positively related to the production, then its deformation influence range can be controlled if the pumping rate has been effectively controlled, and it is generally not more than 1000m. （4） When the high - speed railway through the region of land subsidence prone to take around, the multiple measures should be taken to avoid uneven settlement, such as bypassing centralized pumping region, closing well, limiting the production and controlling the amount of groundwater exploitation. （5） The research results can provide references for line selection of high - speed railway and subsidence control in land subsidence region.
出处
《铁道工程学报》
EI
北大核心
2014年第12期23-27,32,共6页
Journal of Railway Engineering Society
关键词
抽水
地基变形
离心模型试验
数值模拟
影响范围
pumping groundwater
ground settlement
centrifuge model test
numerical simulation
influence scope
