地下水人工回灌和停采对地面沉降控制的影响分析

地面沉降是全世界主要的工程地质灾害之一,而地下水超采是造成地面沉降的主要原因之一。为研究地下水人工回灌和停采对北京平原地面沉降的影响,采用三维地下水模型和情景设计法,设计3个情景(保持现状、人工回灌和地下水停采)对北京平原区域及沉降中心的沉降速率进行模拟。结果表明:保持现状、人工回灌和地下水停采等情景下北京平原在2015、2020和2030年的区域地面沉降分别为24 mm/a左右、12. 7～23. 2 mm/a及12. 4～23. 7mm/a,沉降中心地面沉降分别为39. 30～158. 62 mm/a、21. 09～165. 83 mm/a及16. 5～162. 95 mm/a;人工回灌和地下水停采对研究区地下水水位和含水层储存量的恢复以及地面沉降的控制有显著的促进作用,但地下水停采的效果要优于人工回灌的效果;只有综合考虑社会经济发展和地面沉降控制,才能既控制地面沉降的恶化,又保证北京平原社会的可持续发展。

Effects of groundwater artificial recharge and the termination of groundwater exploitation on land subsidence control

Land subsidence is one of the major engineering geological disasters in the world, while groundwater overexploitation is one of the main causes of land subsidence. In order to study the influence of artificial recharge and the termination of groundwater exploitation on land subsidence of Beijing plain, three scenarios of business as usual(BAU), artificial recharge(AR) and the termination of exploitation(TE) were designed to simulate the regional and central subsidence rate based on the 3D groundwater flow model and scenario analysis method. The results showed that the regional land subsidence rates under the scenarios of BAU, AR, and TE in the Beijing plain in 2015, 2020, and 2030 were about 24 mm/a, 12.7-23.2 mm/a, and 12.4-23.7 mm/a, respectively. The land subsidence rates at the subsidized centers in 2015, 2020, and 2030 were 39.30-158.62 mm/a, 21.09-165.83 mm/a, and 16.5-162.95 mm/a respectively. AR and TE played significant roles in promoting the recovery of groundwater level and aquifer storage as well as the control of land subsidence in the study area, but the effect of TE is better than that of AR. Only by comprehensively considering social and economic development and land subsidence control can the deterioration of land subsidence be controlled and the sustainable development of Beijing plain society be guaranteed.