软土地区多井降水与回灌条件下的土层沉降特征研究  

Study on Subsidence Characteristics under Multi-well Dewatering and Recharging Conditions in Soft Clay

作　　者：肖玉兰[1] XIAO Yulan(China Railway Shanghai Design Institute Group Co.,Ltd.,Shanghai 200070,China)

机构地区：[1]中铁上海设计院集团有限公司,上海200070

出　　处：《铁道勘察》2024年第3期83-88,共6页Railway Investigation and Surveying

摘　　要：为研究软土地区车站基坑降水与回灌引起的土体沉降及土层变形特征,结合上海市域铁路示范区线水乡客厅站抽水试验工程实例,通过分析土体在抽水及回灌作用下的水位变化与土层沉降特征,研究表明,(1)抽水过程中,含水层中上部和上部弱透水层中产生的沉降明显大于抽水含水层下部土层产生的沉降;停止抽水和回灌过程中,抽水含水层中上部和上部弱透水层中产生的回弹明显大于抽水含水层下部土层。(2)抽水期间,地面沉降距离抽水中心愈近,沉降值愈大,远离抽水中心,地面沉降有逐渐减小的趋势;回灌引起的地面回弹与抽水沉降的影响规律并不相同;(3)土层间变形量和含水体层厚和层间岩土体性质密切相关,回弹模量大且层厚大的土层较回弹模量小,且层厚小的土层回弹性效率高,各含水体均存在非线性回弹。In order to study the soil deformation characteristics caused by precipitation and recharging of station foundation pits in soft clay,combined with the pumping test project of Shuixiangketing Station of the Shanghai City Railway Shifanqu Line,the water level changes and characteristics of the soil under pumping and recharging were analyzed.The study shows that:(1)During the pumping process,the generated in the upper and middle weakly permeable layers of the aquifer is significantly greater than that generated in the lower soil layer of the pumped aquifer.During the process of stopping pumping and reinjection,the rebound generated in the upper and weakly permeable layers of the pumped aquifer is significantly greater than that in the lower soil layer of the pumped aquifer.(2)During the pumping period,the closer the ground is to the pumping center,the greater the value will be.As it moves away from the pumping center,the ground tends to gradually decrease.The impact law of ground rebound caused by recharge and pumping is not the same.(3)The deformation between soil layers is closely related to the thickness of water containing layers and the properties of interlayer rock and soil.Soil layers with high rebound modulus and large layer thickness have higher rebound efficiency than those with low rebound modulus and small layer thickness.Nonlinear rebound exists in all water containing layers.

关 键 词：市域铁路 软土地区 抽水 回灌 地面沉降 土体变形 

分 类 号：U239.5[交通运输工程—道路与铁道工程] U212.2[天文地球—地质矿产勘探] P641.73[天文地球—地质学]