拱形双排隔离桩对既有隧道的保护效果研究
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摘要
采用隔离桩来保护邻近基坑的既有隧道是工程中常用方法,目前隔离桩平面排列形式多采用传统的矩形行列式。以杭州市某房建地下室基坑工程为例,提出由直线形排桩和弧形排桩组成的拱形双排隔离桩及相应的优化方案,采用ABAQUS有限元软件建立三维模型,研究了隔离桩中心距、桩半径、平面位置以及弧形排桩曲率半径等因素对隔离效果的影响,并与实测结果进行对比。结果表明:隧道衬砌总位移存在最大值和最小值,隧道衬砌总位移最大值点位于拱底,最小值点位于拱顶,隧道衬砌整体呈现出沉降的趋势。减小隔离桩中心距或增大隔离桩半径均可减小隧道衬砌的位移,拱形双排隔离桩的保护效果优于传统形式;将拱形双排隔离桩设在距基坑10 m处,并将弧形排桩设在隧道一侧更合理;弧形排桩曲率半径对隧道保护效果存在合理值;采用优化方案时隧道位移比原方案减小45.7%,隧道更趋于安全。
Isolated piles are often used to protect existing tunnels at the edge of foundation pits in engineering practices. Currently, traditional rectangular pile layouts are mostly adopted in the arrangement of isolated piles. For the excavation of a building basement in Hangzhou, the arch double row isolated pile, which is composed of straight row piles and curved row piles, and the corresponding optimization scheme were proposed. A three-dimensional model was established by using the finite element software ABAQUS, and the influence of center distance, pile radius,plane position, and radius curvature of pile on the isolation effect was studied, together with a comparison with measured results. The results show that there is a maximum and minimum value of the total displacement of tunnel lining; the maximum total displacement of tunnel lining is located at the arch bottom, the minimum value occurs at the arch top, and the lining of the tunnel shows a general trend of subsidence. A reduction of the center distance and an increase of the pile radius can reduce the tunnel displacement, and the isolation effect of double row piles is better than traditional ones. Moreover, a reasonable arrangement is that the arch double row isolation pile is located at about 10 m away from the foundation pit, and the curved row piles are deployed at one side of the tunnel; there is a critical value of the curvature radius of curved row pile for maximizing the protection effect on the tunnel. Finally, the tunnel displacement is reduced by45. 7% using the optimized scheme as compared to the original scheme, and hence the tunnel tends to be safer.
Isolated piles are often used to protect existing tunnels at the edge of foundation pits in engineering practices. Currently, traditional rectangular pile layouts are mostly adopted in the arrangement of isolated piles. For the excavation of a building basement in Hangzhou, the arch double row isolated pile, which is composed of straight row piles and curved row piles, and the corresponding optimization scheme were proposed. A three-dimensional model was established by using the finite element software ABAQUS, and the influence of center distance, pile radius,plane position, and radius curvature of pile on the isolation effect was studied, together with a comparison with measured results. The results show that there is a maximum and minimum value of the total displacement of tunnel lining; the maximum total displacement of tunnel lining is located at the arch bottom, the minimum value occurs at the arch top, and the lining of the tunnel shows a general trend of subsidence. A reduction of the center distance and an increase of the pile radius can reduce the tunnel displacement, and the isolation effect of double row piles is better than traditional ones. Moreover, a reasonable arrangement is that the arch double row isolation pile is located at about 10 m away from the foundation pit, and the curved row piles are deployed at one side of the tunnel; there is a critical value of the curvature radius of curved row pile for maximizing the protection effect on the tunnel. Finally, the tunnel displacement is reduced by45. 7% using the optimized scheme as compared to the original scheme, and hence the tunnel tends to be safer.
引文
[1]孔祥鹏,刘国彬,廖少明.明珠线二期上海体育馆地铁车站穿越施工对地铁一号线车站的影响[J].岩石力学与工程学报,2004,23(5):821-825.Kong X P,Liu G B,Liao Sh M.Influence of construction of Shanghai Stadium transverse station of Pearl Line phase II on station of metro line No.1[J].Chinese Journal of Rock Mechanics and Engineering,2004,23(5):821-825.(in Chinese)
[2]Chang C T,Sun C W,Duann S W.Response of a Taipei Rapid Transit System(TRTS)tunnel to adjacent excavation[J].Tunneling and Underground Space Technology,2001,16(13):151-158.
[3]Shi J U,Ng C W W,Chen Y H.Three-dimensiotal numerical parametric study of the influetce of basemeit excavation on existing tunnel[J].Computers and Geotechnics,2015,63(1):146-158.
[4]Dolezalova M.Tunnel complex unloaded by a deep exGavation[J].Computers and Geotechnics,2001,28(3):469-493.
[5]Sharma J S,Hefny A M,Zhao J,et al.Effect of large excavation on deformation of adjacent MRT tunnels[J].Tunneling and Underground Space Technology,2001,16(2):93-98.
[6]罗成恒,魏建华.减少软土深基坑周边环境初始位移的方法探讨[J].岩土工程学报,2012,34(增):49-53.Luo Ch H,Wei J H.Method for decreasing initial displacement of surrounding environment of deep excavations in soft soils[J].Chinese Journal of Geotechnical Engineering,2012,34(Sup):49-53.(in Chinese)
[7]竺明星,龚维明,徐国平,等.大面积堆载作用下轴向受力隔离桩的承载机制分析[J].岩石力学与工程学报,2014,33(2):421-432.Zhu M X,Gong W M,Xu G P,et al.Analysis of bearing mechanism of axially loaded isolation piles under large-scale surcharge loading[J].Chinese Journal of Rock Mechanics and Engineering,2014,33(2):421-432.(in Chinese)
[8]竺明星,王磊,龚维明.边载作用下隔离桩隔离效果的影响因素研究[J].岩土工程学报,2014,36(4):671-679.Zhu M X,Wang L,Gong W M.Factors influencing isolation effects of isolation piles under side loading[J].Chinese Journal of Geotechnical Engineering,2014,36(4):671-679.(in Chinese)
[9]应宏伟,李涛,杨永文,等.深基坑隔断墙保护邻近建筑物的效果与工程应用分析[J].岩土工程学报,2011,33(7):1 123-1 128.Ying H W,Li T,Yang Y W,et al.Effect and application walls in protecting adjacent buildings from deep foundation pits[J].Chinese Journal of Geotechnical Engineering,2011,33(7):1 123-1 128.(in Chinese)
[10]王辉.拱形抗滑桩墙结构体系工作性能试验研究[D].西安:长安大学,2011.Wang H.Experimental study on working performance of arch anti slide pile wall structure system[D].Xi'-an:Chang'an University,2011.(in Chinese)
[11]耿大新,余小强,童立红,等.弧形地连墙侧位移计算的新方法[J].岩土工程学报,2016,38(12):2 272-2 277.Geng D X,Yu X Q,Tong L H,et al.New method for calculating lateral displacement of curved ground wall[J].Chinese Journal of Geotechnical Engineering,2016,38(12):2 272-2 277.(in Chinese)
[12]王在军.拱形双排抗滑桩滑坡推力分配计算及其工程应用[D].长沙:中南大学,2013.Wang Z J.Calculation and engineering application of the thrust distribution of double row anti slide piles[D].Changsha:Central South University,2013.(in Chinese)
[13]Zhang Z G,Huang M S,Wang W D.Evaluation of deformation response for adjacent tunnels due to soil unloading in excavation engineering[J].Tunnelling and Underground Space Technology,2013,38(9):244-253.
[14]Wei G,Hu L W,Chen K L.Numerical simulation of effect of foundation pit excavation on underlain shield tunnel[J].Applied Mechanics and Materials,2014(580-583):1 001-1 007.
[15]城市轨道交通结构安全保护技术规范:CJJ/T 202-2013[S].北京:中国建筑工业出版社,2013.Technical code for protection structure of urban rail transit:CJJ/T 202—2013[S].Beijing:China Architecture&Building Press,2013.(in Chinese)
[16]成守泽.长短桩组合围护结构工作机理研究[D].杭州:浙江大学,2013.Cheng Sh Z.The mechanism research on retaining structure with long and short pile combination[D].Hangzhou:Zhejiang University,2013.(in Chinese)
[17]王金昌,陈页开.ABAQUS在土木工程中的应用[M].杭州:浙江大学出版社,2006:89-95.Wang J Ch,Chen Y K.Application of ABAQUS in civil engineering[M].Hangzhou:Zhejiang University Press,2006:89-95.(in Chinese)
[18]费康,张建伟.ABAQUS在岩土工程中的应用[M].北京:中国水利水电出版社,2013:115-126.Fei K,Zhang J W.Application of ABAQUS in geotechnical engineering[M].Beijing:China Water&Power Press,2013:115-126.(in Chinese)
[19]陈卫忠,伍国军,贾善坡.ABAQUS在隧道及地下工程中的应用[M].北京:中国水利水电出版社,2013:58-82.Chen W Zh,Wu G J,Jia Sh P.Application of ABAQUS in tunnel and underground engineering[M].Beijing:China Water&Powe Press,2013:58-82.(in Chinese)
[20]建筑边坡工程技术规范:GB 550330-2002[S].北京:中国建筑工业出版社,2002.Construction of slope engineering and technical specification:GB 550330—2002[S].Beijing:China Building Industry Press,2002.(in Chinese)
[2]Chang C T,Sun C W,Duann S W.Response of a Taipei Rapid Transit System(TRTS)tunnel to adjacent excavation[J].Tunneling and Underground Space Technology,2001,16(13):151-158.
[3]Shi J U,Ng C W W,Chen Y H.Three-dimensiotal numerical parametric study of the influetce of basemeit excavation on existing tunnel[J].Computers and Geotechnics,2015,63(1):146-158.
[4]Dolezalova M.Tunnel complex unloaded by a deep exGavation[J].Computers and Geotechnics,2001,28(3):469-493.
[5]Sharma J S,Hefny A M,Zhao J,et al.Effect of large excavation on deformation of adjacent MRT tunnels[J].Tunneling and Underground Space Technology,2001,16(2):93-98.
[6]罗成恒,魏建华.减少软土深基坑周边环境初始位移的方法探讨[J].岩土工程学报,2012,34(增):49-53.Luo Ch H,Wei J H.Method for decreasing initial displacement of surrounding environment of deep excavations in soft soils[J].Chinese Journal of Geotechnical Engineering,2012,34(Sup):49-53.(in Chinese)
[7]竺明星,龚维明,徐国平,等.大面积堆载作用下轴向受力隔离桩的承载机制分析[J].岩石力学与工程学报,2014,33(2):421-432.Zhu M X,Gong W M,Xu G P,et al.Analysis of bearing mechanism of axially loaded isolation piles under large-scale surcharge loading[J].Chinese Journal of Rock Mechanics and Engineering,2014,33(2):421-432.(in Chinese)
[8]竺明星,王磊,龚维明.边载作用下隔离桩隔离效果的影响因素研究[J].岩土工程学报,2014,36(4):671-679.Zhu M X,Wang L,Gong W M.Factors influencing isolation effects of isolation piles under side loading[J].Chinese Journal of Geotechnical Engineering,2014,36(4):671-679.(in Chinese)
[9]应宏伟,李涛,杨永文,等.深基坑隔断墙保护邻近建筑物的效果与工程应用分析[J].岩土工程学报,2011,33(7):1 123-1 128.Ying H W,Li T,Yang Y W,et al.Effect and application walls in protecting adjacent buildings from deep foundation pits[J].Chinese Journal of Geotechnical Engineering,2011,33(7):1 123-1 128.(in Chinese)
[10]王辉.拱形抗滑桩墙结构体系工作性能试验研究[D].西安:长安大学,2011.Wang H.Experimental study on working performance of arch anti slide pile wall structure system[D].Xi'-an:Chang'an University,2011.(in Chinese)
[11]耿大新,余小强,童立红,等.弧形地连墙侧位移计算的新方法[J].岩土工程学报,2016,38(12):2 272-2 277.Geng D X,Yu X Q,Tong L H,et al.New method for calculating lateral displacement of curved ground wall[J].Chinese Journal of Geotechnical Engineering,2016,38(12):2 272-2 277.(in Chinese)
[12]王在军.拱形双排抗滑桩滑坡推力分配计算及其工程应用[D].长沙:中南大学,2013.Wang Z J.Calculation and engineering application of the thrust distribution of double row anti slide piles[D].Changsha:Central South University,2013.(in Chinese)
[13]Zhang Z G,Huang M S,Wang W D.Evaluation of deformation response for adjacent tunnels due to soil unloading in excavation engineering[J].Tunnelling and Underground Space Technology,2013,38(9):244-253.
[14]Wei G,Hu L W,Chen K L.Numerical simulation of effect of foundation pit excavation on underlain shield tunnel[J].Applied Mechanics and Materials,2014(580-583):1 001-1 007.
[15]城市轨道交通结构安全保护技术规范:CJJ/T 202-2013[S].北京:中国建筑工业出版社,2013.Technical code for protection structure of urban rail transit:CJJ/T 202—2013[S].Beijing:China Architecture&Building Press,2013.(in Chinese)
[16]成守泽.长短桩组合围护结构工作机理研究[D].杭州:浙江大学,2013.Cheng Sh Z.The mechanism research on retaining structure with long and short pile combination[D].Hangzhou:Zhejiang University,2013.(in Chinese)
[17]王金昌,陈页开.ABAQUS在土木工程中的应用[M].杭州:浙江大学出版社,2006:89-95.Wang J Ch,Chen Y K.Application of ABAQUS in civil engineering[M].Hangzhou:Zhejiang University Press,2006:89-95.(in Chinese)
[18]费康,张建伟.ABAQUS在岩土工程中的应用[M].北京:中国水利水电出版社,2013:115-126.Fei K,Zhang J W.Application of ABAQUS in geotechnical engineering[M].Beijing:China Water&Power Press,2013:115-126.(in Chinese)
[19]陈卫忠,伍国军,贾善坡.ABAQUS在隧道及地下工程中的应用[M].北京:中国水利水电出版社,2013:58-82.Chen W Zh,Wu G J,Jia Sh P.Application of ABAQUS in tunnel and underground engineering[M].Beijing:China Water&Powe Press,2013:58-82.(in Chinese)
[20]建筑边坡工程技术规范:GB 550330-2002[S].北京:中国建筑工业出版社,2002.Construction of slope engineering and technical specification:GB 550330—2002[S].Beijing:China Building Industry Press,2002.(in Chinese)