岩土力学
巖土力學
암토역학
ROCK AND SOIL MECHANICS
2010年
2期
577-581,587
,共6页
魏龙海%王明年%赵东平%吉艳雷
魏龍海%王明年%趙東平%吉豔雷
위룡해%왕명년%조동평%길염뢰
海底隧道%监控量测%结构变形%大跨度隧道
海底隧道%鑑控量測%結構變形%大跨度隧道
해저수도%감공량측%결구변형%대과도수도
subsea tunnel%monitoring measurement%structure deformation%large-span tunnel
翔安隧道是我国第一条大跨公路海底隧道,其两端陆域段位于富水的强风化岩层中,地质条件极为复杂.隧道施工期间,部分断面发生了较大变形,超过了预留变形量,给二次衬砌的施工造成了影响,而且过大的变形有时还会导致隧道围岩失稳,应寻求一套合理的变形控制措施.基于现场监测数据和施工记录,并结合数值方法,对隧道施工过程中所采取的工程措施的作用效果进行了研究.结果表明,增设锁脚锚管、加强临时支护及管井降水等工程措施都可以在一定程度上减小隧道支护结构的变形,但在地质条件较差的富水强风化岩层中修建大跨公路隧道时,将两种或多种工程措施的组合起来使用效果更佳.例如,在采用降水(连续墙)+加强临时支护+锁脚锚管的组合方案后,隧道的拱顶下沉减小了46 %~60 %,水平收敛也减小了约30 %.这些措施可为今后类似工程提供一定的参考.
翔安隧道是我國第一條大跨公路海底隧道,其兩耑陸域段位于富水的彊風化巖層中,地質條件極為複雜.隧道施工期間,部分斷麵髮生瞭較大變形,超過瞭預留變形量,給二次襯砌的施工造成瞭影響,而且過大的變形有時還會導緻隧道圍巖失穩,應尋求一套閤理的變形控製措施.基于現場鑑測數據和施工記錄,併結閤數值方法,對隧道施工過程中所採取的工程措施的作用效果進行瞭研究.結果錶明,增設鎖腳錨管、加彊臨時支護及管井降水等工程措施都可以在一定程度上減小隧道支護結構的變形,但在地質條件較差的富水彊風化巖層中脩建大跨公路隧道時,將兩種或多種工程措施的組閤起來使用效果更佳.例如,在採用降水(連續牆)+加彊臨時支護+鎖腳錨管的組閤方案後,隧道的拱頂下沉減小瞭46 %~60 %,水平收斂也減小瞭約30 %.這些措施可為今後類似工程提供一定的參攷.
상안수도시아국제일조대과공로해저수도,기량단륙역단위우부수적강풍화암층중,지질조건겁위복잡.수도시공기간,부분단면발생료교대변형,초과료예류변형량,급이차츤체적시공조성료영향,이차과대적변형유시환회도치수도위암실은,응심구일투합리적변형공제조시.기우현장감측수거화시공기록,병결합수치방법,대수도시공과정중소채취적공정조시적작용효과진행료연구.결과표명,증설쇄각묘관、가강림시지호급관정강수등공정조시도가이재일정정도상감소수도지호결구적변형,단재지질조건교차적부수강풍화암층중수건대과공로수도시,장량충혹다충공정조시적조합기래사용효과경가.례여,재채용강수(련속장)+가강림시지호+쇄각묘관적조합방안후,수도적공정하침감소료46 %~60 %,수평수렴야감소료약30 %.저사조시가위금후유사공정제공일정적삼고.
Xiang'an subsea tunnel is the first subsea tunnel in China; and its geological conditions are complex and unfavorable with enriched groundwater.During the tunnel construction,the deformation of tunnel support is great; and it has brought the bad-effect on the construction of quadric lining; moreover,the large deformation maybe bring on the surrounding rock collapse.It is important to seek for a reasonable countermeasure to restrict the large deformation to ensure safety construction.Focused on Xiang'an subsea tunnel,field monitoring data and construction annel are analyzed and numerical calculation is employed.Some measures and its combination against abnormal deformation during the tunnel construction are taken.The analytical results indicate that,to some extent,the countermeasure including setting locking anchor pipe,enhancing stiffness and intensity of temporary support,constructing continuous wall for groundwater proof,can decrease the displacements of the tunnel support.But the effection of using the combination project is better during constructing the large-span tunnel in the complex geological conditions.For example,after adopting the seventh combination project,arch crown settlement will be reduced 46-60%; and horizontal convergence will be reduced about 30%.The analytical method and result can provide references to the other similar engineering cases.