- 摘 要
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(1 南通城市軌道交通有限公司, 南通 226000; 2 同濟大學(xué)土木工程學(xué)院, 上海 200092)
摘要: 以富水砂性地層順作法地鐵車站基坑為工程背景,結(jié)合施工現(xiàn)場監(jiān)測數(shù)據(jù),對圍護結(jié)構(gòu)側(cè)向位移變形、周邊地表沉降、地下水水位變化及周邊建筑物沉降進行分析,總結(jié)富水砂性地層的變形性狀和對周邊環(huán)境的影響.監(jiān)測數(shù)據(jù)和分析結(jié)果表明:富水砂性地層條件下,地下連續(xù)墻最大側(cè)向位移 δhm 的變化范圍為 0. 045%H~ 0. 5%H,均值約為 0. 22%H,發(fā)生位置在(H-4,H+10)之間;基坑開挖引起的地表沉降影響范圍在 35m 以內(nèi),約 2 倍基坑開挖深度;墻后地表最大沉降發(fā)生在距離基坑 5~ 10m 左右;富水砂性地層有著地下水位高,滲透性強的特點,施工中采用疏干降水與承壓降水相結(jié)合的措施可以有效控制地下水位變化;施工建設(shè)過程中對周邊建筑物進行實時監(jiān)測來反饋指導(dǎo)施工, 可以保證施工對周邊建筑物的影響在可控范圍內(nèi).
關(guān)鍵詞: 富水砂性地層; 地鐵車站; 深基坑; 基坑降水; 變形; 監(jiān)測
中圖分類號:TU758. 11 文獻標(biāo)志碼:A 文章編號:1002-848X(2023)12-0138-06
DOI:10. 19701 / j. jzjg. 20201613
Analysis on monitoring and deformation of subway deep foundation pit inwater-rich sand stratum
WAN Jing1, FAN Dongdong2, LIU Tianren2, TAN Yong2
(1 Nantong City Rail Transit Co. , Ltd. , Nantong 226000, China; 2 Department of Geotechnical Engineering, TongjiUniversity, Shanghai 200092, China)
Abstract: Taking the foundation pit of subway station with water-rich sand stratum as the engineering background, combinedwith the monitoring data on the construction site, the lateral displacement deformation of the enclosure structure, thesurrounding surface settlement, the groundwater level change and the settlement of surrounding buildings were analyzed tosummarize the deformation behavior of the water-rich sand stratum and its impact on the surrounding environment. Themonitoring data and analysis results show that: under the conditions of water-rich sand stratum, the maximum lateraldisplacement δhmof the diaphragm wall ranges from 0. 045%H to 0. 5%H, with an average value of about 0. 22%H,and theoccurrence is between (H-4, H+10). The impact of surface settlement caused by excavation of foundation pit ranges within35m, about 2 times the excavation depth of the foundation pit. The maximum settlement of the surface behind the wall occursat a distance of about 5 ~ 10m from the foundation pit. The water-rich sandy stratum has the characteristics of highgroundwater level and strong permeability, and the combination of pumping in phreatic and confined aquifers can effectivelycontrol the change of groundwater level in construction; real-time monitoring of surrounding buildings during construction canguide construction, which ensures that the impact of construction on surrounding buildings is within a controllable range.
Keywords:water-rich sand stratum; subway statio; deep foundation pit; dewatering of foundation pit; deformation; monitoring
第一作者:萬晶,博士,工程師,主要從事基坑工程方面的研究,Email:706505658@ qq. com.
[引用本文] 萬晶,樊冬冬,劉天任,等. 富水砂性地層地鐵深基坑監(jiān)測及變形分析[ J]. 建筑結(jié)構(gòu),2023,53(12):138-143. WAN Jing,FAN Dongdong,LIU Tianren,et al. Analysis on monitoring and deformation of subway deep foundationpit in water-rich sand stratum[J]. Building Structure,2023,53(12):138-143.
