【摘要】 采用真空技术进行工程地下水处理被广泛应用于北京地铁建设中。目前对于由真空降水引起地面沉降的计算方法研究尚不充分。通过运用位移法解弹性力学半空间问题,将真空负压引起的沉降和潜水层、承压含水层降水引起的沉降结合进行分析,得到了简明的沉降计算方法。在北京地铁10号线安定路—北土城路区间进行了现场实验,对在不同距离不同深度的真空度、水位、地表沉降和分层沉降进行了测试和分析。理论分析和现场实验数据都说明了真空负压对地表沉降的影响很小,真空负压引起的地表沉降为0.69 mm,真空降水实验结束时测得最大总沉降量为2.5 mm,满足沉降要求。因此,在相似地层的降水工程中可不考虑真空负压引起的地面沉降。更多还原

【Abstract】 Engineering groundwater treatment using vacuum technology had been widely used in Beijing subway construction But the settlement calculation method of vacuum dewatering was not sufficient.In this paper,the settlement caused by vacuum was calculated by solving half-space elasticity mechanics problem using displacement method.The whole settlement of the soil surface was worked out by adding the settlement caused by phreatic aquifer and confined aquifer dewatering to the settlement caused by vacuum.A field experiment in the Anding Road to Beitucheng Road of Beijing subway was carried out,and the vacuum degree,water level,ground settlement and layered settlement of soil in different distance and depth were monitored and analyzed.The theoretical analysis and experiment data both proved that the ground settlement caused by vacuum pressure was little,with a value of 0.69 mm caused by vacuum pressure and 2.5 mm of total settlement in field experiment.Therefore,the ground settlement caused by vacuum pressure can be neglected when conducting the vacuum dewatering project under similar geological condition.更多还原