盾构进出洞是地铁隧道建造过程中关键风险点,因此软弱地层盾构始发端头土体均需加固,以确保盾构始发施工安全。笔者以南京宁和城际轨道交通工程天河路站左线盾构始发端头工程为背景,研究了盾构端头土体加固方式、垂直局部冻结补强加固封水方案,以及实测内容、测温孔和测点位置布设、探孔检验和布置方式,并进行了冻结实测及温度发展规律分析,提出了盾构始发时冻结实测应满足的条件。垂直冻结加固与实测工程实践表明:冻结期间停机对冻结影响很大,停机后恢复温度所需时间是停机时间的2～3倍; 采用垂直局部冻结方式、双排冻结管冻结施工方案和工艺是合理有效的,在第1排冻结管与地连墙间、两排冻结管间及外排冻结管外侧布设测温孔,通过探孔实测冻结效果等验证冻结实测方案安全可靠。
Abstract
Shield launching and receiving are the key risk points in process of building subway tunnel, so the soft soil around the tunnel shield-launching end must be reinforced in order to ensure the shield launches safely. This paper took the left tunnel shield-launching end of Tianhe Road station Ning-he intercity rail in Nanjing City as background. The methods of soil reinforcement, the schemes of vertical partial freezing reinforcement to blocking water, the contents of monitoring, the layouts of temperature measuring tubes and measuring points, the layouts of probe holes, and the methods of inspection for tunnel shield-launching end were all put forward. The laws of temperature development were analyzed after the completion of monitoring in site, in addition, the necessary conditions which the monitoring in site should meet were put forward when shield began launching. The vertical freezing and the actual engineering practices proved that refrigerator shutdown would have a marked impact on freezing period, and recovery time was 2-3 times shutdown time. The methods of vertical partial freezing, and the layouts of double rows of freezing pipes were reasonable and effective. The monitoring schemes of laying temperature measuring tubes between the first row of freezing pipes and the diaphragm walls, between two rows of freezing pipes, outside of the outer rows of freezing pipes, and the methods of verifying freezing effect by experimental drilling were safe and reliable.
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
参考文献
[1] 杨平,袁云辉,佘才高,等.南京地铁集庆门盾构隧道进洞端头人工冻结加固温度实测[J].解放军理工大学学报:自然科学版,2009,10(6):591-596.
Yang P,Yuan Y H,She C G,et al. Temperature study on artificial soil freezing reinforcement for shield entry in Jiqing-men station of Nanjing metro[J]. Journal of PLA University of Science and Technology:Nature Science Edition,2009,10(6):591-596.
[2] 张奇,杨树才,王明洋.结合南京地铁2号线谈盾构施工风险源[J].施工技术,2009,38(1):42-44.
Zhang Q,Yang S C,Wang M Y.Discussion on risk sources of shield construction in Nanjing metro Line 2[J].Construction Technology,2009,38(1):42-44.
[3] 胡俊.高水压砂性土层地铁大直径盾构始发端头加固方式研究[D].南京:南京林业大学,2012.
Hu J.Study on the reinforcement methods of subway large-diameter shield launching in the sandy clay with high water pressure[D]. Nanjing:Nanjing Forestry Universty,2012.
[4] 杨纪彦.超大直径泥水盾构冷冻始发施工技术[J].现代隧道技术,2010,47(3):60-66.
Yang J Y. Freezing technology for the launching of a super-large diameter slurry shield[J]. Modern Tunnelling Technology,2010,47(3):60-66.
[5] 李攀,谢雄耀.上海长江隧道冻结监测优化设计及数据分析[J].地下空间与工程学报,2012,8(1):122-128.
Li P,Xie X Y. Research on optimization of freezing-temperature monitoring design and method of data analysis in Shanghai Yangtze River tunnel[J]. Chinese Journal of Underground Space and Engineering,2012,8(1):122-128.
[6] 武冰冰,蔡海兵,程桦.地铁隧道盾构洞门的垂直冻结加固技术[J].铁道标准设计,2011(9):80-84.
Wu B B,Cai H B,Cheng H. Technology of vertical freezing consolidation for shield launching portal of subway tunnel[J]. Railway Standard Design,2011(9):80-84.
[7] Yang P,Zhu F B. Application of freezing method to recover tunnel accident in complex stratum of Nanjing subway[C]//International conference on geotechnical engineering for disaster mitigation & rehabilitation. Singapore: World Scientific Publishing Company,2005.
[8] Yang P,Ke J M,Wang J G,et al. Numerical simulation of frost heave with coupled water freezing temperature and stress fields in tunnel excavation[J]. Computers and Geotechnics,2006,33(6):330-340.
[9] 胡俊.盾构隧道端头垂直冻结加固不同冻结管直径的温度场数值分析[J].铁道建筑,2014(9):56-59.
Hu J. Numerical analysis of temperature field of different diameter freezing pipes in vertical freezing reinforcement for shield tunnel end[J]. Railway Engineering,2014(9):56-59.
[10] 魏龙海,郭小红,乔春江,等.南京纬三路大直径越江盾构隧道冻结法出洞方案研究[J].现代隧道技术,2011,48(3):80-86.
Wei L H,Guo X H,Qiao C J,et al. Study on freezing method applied for large diameter river-crossing shield tunnel in Nanjing City[J]. Modern Tunnelling Technology,2011,48(3):80-86.
[11] 王杰,杨平,张翔宇,等.水平冻结水泥土加固盾构洞门温度场敏感性分析[J].南京林业大学学报:自然科学版,2013,37(3):145-151.
Wang J,Yang P,Zhang X Y,et al. Sensitivity study of soil thermal field in horizontal freezing shield portal reinforced by cement[J].Journal of Nanjing Forestry University:Natural Sciences Edition,2013,37(3):145-151.
[12] 胡向东,汪洋.三排管冻结温度场的势函数叠加法解析解[J].岩石力学与工程学报,2012,31(5):1071-1080.
Hu X D,Wang Y.Analytical solution of three-row-piped frozen temperature field by means of superpposition of potential function[J].Chinese Journal of Rock Mechanics and Engineering,2012,31(5):1071-1080.
[13] 陈广峰,陈惠芳,程千元,等.垂直局部冷冻施工工艺在盾构进洞中的应用[J].施工技术,2012,41(15):84-87.
Chen G F,Chen H F,Cheng Q Y,et al.Application of vertical local freezing method in the construction of shield entering cave[J].Construction Technology,2012,41(15):84-87.
[14] 张婷,杨平,王效宾.浅表土人工冻土冻胀特性的研究[J].南京林业大学学报:自然科学版,2010,34(4):65-68.
Zhang T,Yang P,Wang X B. Experimental research on the frost heave behavior of shallow top soil[J]. Journal of Nanjing Forestry University:Natural Sciences Edition,2010,34(4):65-68.
[15] 沈季良,崔云龙,王介峰,等.建井工程手册:第4卷[M].北京:煤炭工业出版社,1986.
Shen J L,Cui Y L,Wang J F,et al.Construction Engineering Handbook(volume fourth)[M].Beijing:China Coal Industry Publishing House,1986.
基金
收稿日期:2015-01-26 修回日期:2015-06-27
基金项目:住建部科研项目(2014-k3-029); 泰州市科技支撑计划(TS201522)
第一作者:石泉彬,副教授。*通信作者:杨平,教授。E-mail: yangping@njfu.edu.cn。
引文格式:石泉彬,杨平,张婷,等. 软弱地层盾构始发端头的垂直冻结加固与实测[J]. 南京林业大学学报:自然科学版,2015,39(6):125-130.
PDF(2034027 KB)
