为消除管节间差异沉降,港珠澳大桥岛—隧过渡段沉管基础采用挤密砂桩+堆载预压的地基处理方式。详细介绍了采用液体压差式沉降仪监测沉管隧道基础沉降的应用技术,并获得了较好的复合地基沉降数据。采用多种技术手段保证仪器埋设成功率,包括作业时机选择、导线接头及导线保护等。对试验结果进行分析,结果表明该技术运行稳定性高、数据误码率低、不易受风浪及施工干扰,可实现对沉管基础的连续稳定无线监测。
Abstract
The island-tunnel segment of Hong Kong-Zhuhai-Macau Bridge is featured with deep soft soil under the immersed tube foundation. Sand compaction pile together with preloading was adopted to eliminate the differential settlement between joint parts. In this paper, the technique of monitoring tube foundation settlement by liquid pressure settlement sensor is introduced in details. Satisfactory settlement data was obtained. A variety of technical approaches, including the timing of operations, protection of wire connectors and wire, were employed to improve the success rate of equipment burying. Test results showed that the technique could perform continuous stable wireless monitoring as it is of high stability, low error rate, and is less susceptible to wind and waves and construction interferences. Therefore it could realize the continuous and stable wireless monitoring of the foundation. The study is expected to provide reference for the monitoring of composite foundation under deep water conditions.
关键词
港珠澳大桥沉管隧道 /
挤密砂桩 /
堆载预压 /
沉降计算 /
原位测试
Key words
immersed tube tunnel of Hong Kong-Zhuhai-Macau Bridge /
sand compaction pile /
preloading /
settlement calculation /
in situ test
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
参考文献
[1] 林 鸣,梁 桁,刘晓东,等.海上挤密砂桩工法及其在港珠澳大桥岛隧工程的应用[J].中国港湾建设,2012,(4): 72-77.
[2] HEO Y, JEONG G C, BAE W S. Evaluation of the Effect of Penetration Ratios on Composite Grounds Improved with Sand Compaction Piles[J].Marine Georesources & Geotechnology,2015,33(3):253-263.
[3] 莫景逸,黄晋申.挤密砂桩在海洋接岸地基加固工程中的应用[J].水运工程,2007,(11):123-128.
[4] 任文峰,王星华,韩晓飞.高速铁路软土路基沉降试验研究[J].水利与建筑工程学报,2010,8(4):65-68.
[5] 朱森林.堆载预压技术在潮汕机场大面积深厚软土地基处理中的应用[J].长江科学院院报,2014,31(9):43-46.
[6] 解林博,许 浩,陈运涛,等.海上构筑物地基自动监测系统在深水中的密封保护措施[J].中国港湾建设,2013,(2): 40-43.
[7] 中交天津港湾工程研究院有限公司.具有水下无线传输系统的海上构筑物自动监测技术方法:中国,ZL201010149403.4 [P].2011-07-27.
[8]CHUNG S G, KWEON H J, JANG W Y. Observational Method for Field Performance of Prefabricated Vertical Drains[J].Geotextiles and Geomembranes,2014,42(4):405-416.
[9] 王延宁,蒋斌松,于 健,等.港珠澳大桥岛隧结合段高压旋喷桩地基沉降试验及研究[J].岩石力学与工程学报,2017,36(6):1514-1521.
[10]TAN T S, INOUE T, LEE S L. Hyperbolic Method for Consolidation Analysis[J].Journal of Geotechnical Engineering,1991,117(11): 1723-1737.
[11]ASAOKA A. Observational Procedure of Settlement Prediction[J].Soils & Foundations,1978,18(4): 87-101.
[12]TERZAGHI K, PECK R B, MESRI G. Soil Mechanics in Engineering Practice[M]. New Jersey:John Wiley & Sons, 1996:105-107.
[13]JGJ 79—2012,建筑地基处理技术规范 [S]. 北京:中国建筑工业出版社,2012:148.
[14]龚晓南.复合地基理论及工程应用[M]. 北京: 中国建筑工业出版社, 2007: 56-57.
[15]王延宁,蒋斌松,胥新伟,等.挤密砂桩加固水下软土大型原位载荷试验研究[J].岩土力学,2015,36(增1):320-326.
[16]ABOSHI H,MIZUNO Y, KUWABARA M.Present State of Sand Compaction Pile in Japan[J].Deep Foundation Improvements: Design,Construction,and Testing,1991:32-46.
基金
国家自然科学基金项目(51204168,51574223);国家科技支撑计划课题(2011BAG07B02)