摘要
黄土地层中城市地铁隧道水环境变化主要体现在地下水位升降和盾构衬砌管片渗水,地层中水位的变化及管片渗漏会进一步影响地表沉降。以某地铁区间隧道为背景,采用修正摩尔库仑模型(MM-C模型)和DP模型来描述复杂加卸载条件下的地层隆沉问题,并深入研究水环境变化下地表沉降规律。结果表明:盾构管片渗漏比从0.1增大到10期间,地表沉降增加了24%;管片渗漏块数从1增大到6块时,地表最大沉降增大了77%;地下水位下降5 m期间,地表最大沉降增大了1.2倍,水位降深每增加1 m,地表下沉量增加约7 mm;初始水位高度抬升5 m期间,地表最大沉降减小了37%。为了控制地表不发生过量隆沉,渗漏块数不宜超过3块,并应避免拱底管片发生破坏或渗漏,地下水位的回灌抬升高度及降水深度宜分别控制在3.0 m和2.0 m以内。
The change of water environment in urban subway tunnel in loess stratum is mainly reflected in the fluctuation of groundwater level and the seepage of shield lining segments,which will further affect the surface settlement.Based on the background of a subway tunnel,the modified Mohr-Coulomb model(MM-C model)are used to describe the ground surface uplift and ssettlement under complex loading and unloading conditions.The results are as follows.The surface settlement increases by 24%when the shield segment leakage ratio increases from 0.1 to 10.The maximum surface settlement increases by 77%when the number of segment leakage blocks increases from 1 to 6.The maximum surface settlement enlarges by 1.2 times during 5 m groundwater level decline,and the surface settlement increased by about 7 mm with 1m water level decline.During the initial elevation of 5 m,the maximum surface settlement decreased by 37%.In order to control the surface from excessive uplift and settlement,the number of leakage blocks should not exceed 3,and the failure or leakage of arch bottom segments should be avoided.The recharge elevation of groundwater level and the dewatering depth should be controlled within 3.0 m and 2.0 m respectively.
作者
赵爱军
曾华
樊鑫尚
于永堂
彭森
朱才辉
ZHAO Aijun;ZENG Hua;FAN Xinshang;YU Yongtang;PENG Sen;ZHU Caihui(China Railway Urban Development Investment Group Co.,Ltd.,Chengdu,Sichuan 610218,China;China Railway New Silk Road Construction Investment Management Co.,Ltd.,Xi'an,Shaanxi 710038,China;Xi'an University of Architecture and Technology,Xi'an,Shaanxi 710055,China;Zhonglian Northwest Engineering Design&Research Institute Co.,Ltd.,Xi'an,Shaanxi 710077,China;Institute of Geotechnical Engineering,Xi'an University of Technology,Xi'an,Shaanxi 710048,China)
出处
《水利与建筑工程学报》
2024年第5期1-9,16,共10页
Journal of Water Resources and Architectural Engineering
基金
国家自然科学基金(52279110)。
关键词
黄土地层
城市地铁隧道
水环境
数值模拟
地表沉降
loess stratum
urban subway tunnel
water environment
numerical simulation
surface settlement
