考虑施工过程的浅埋软弱隧道管棚变形预测及参数敏感性分析
|
摘要
目前的隧道管棚计算方法和理论解析存在计算繁杂,计算参数的选择对分析结果的正确性影响较大且无法获得精确的理论解或简化的计算公式等问题。文章基于Winkler弹性地基梁理论,考虑隧道施工过程中围岩扰动特性、支护未封闭不完全承载特性、地层反力系数差异特性及荷载分布不均匀特性,建立了管棚超前预支护变形理论计算模型,并通过求解24阶方程组获得超前管棚预支护理论解析。结果表明:1)解析解与数值解和现场实测值吻合度较高,解析解可用于管棚变形预测;2)管棚直径、开挖进尺、地层反力系数均存在最优参数取值,环向间距与管棚变形呈正比例关系,管棚长度并非越长越好,只需满足管棚远端超前掌子面前方2倍台阶高度即可;3)实际施工过程中,通过调整管棚参数来控制隧道拱顶沉降效果从优到劣的顺序为:开挖进尺、注浆改善地层力学性质、环向间距、直径、长度。
In view of the complexities of existing calculation methods and theories for tunnel pipe roof,effects of calculation parameters on analysis results and difficulties to obtain accurate theoretical solution or simplified calculation formula,a theoretical calculation model for predicting deformation of pipe roof as pre-support was established based on Winkler elastic foundation beam theory and considering the disturbance characteristics of surrounding rock,incomplete load bearing behavior due to unclosed support,differences of strata reaction coefficients and uneven load distribution,and a theoretical solution was obtained by solving 24 order equations.The results show that:(1)The analytical solution agrees well with numerical simulation value and field data,and it can be used to predict deformation of pipe roof;(2)it is available to have the optimal parameters of diameter,advance rate and strata reaction coefficient of pipe roof,the circumferential spacing is directly proportional to pipe roof deformation,it meets the requirement only if the length of pipe roof at the far end is not less than two times of the bench height in front of working face;(3)The sequences of controlling effect of vault settlement by adjusting pipe parameters are advance rate,strata mechanical behavior improvement by grouting,circumferential spacing,diameter and length in the order from good to bad.
In view of the complexities of existing calculation methods and theories for tunnel pipe roof,effects of calculation parameters on analysis results and difficulties to obtain accurate theoretical solution or simplified calculation formula,a theoretical calculation model for predicting deformation of pipe roof as pre-support was established based on Winkler elastic foundation beam theory and considering the disturbance characteristics of surrounding rock,incomplete load bearing behavior due to unclosed support,differences of strata reaction coefficients and uneven load distribution,and a theoretical solution was obtained by solving 24 order equations.The results show that:(1)The analytical solution agrees well with numerical simulation value and field data,and it can be used to predict deformation of pipe roof;(2)it is available to have the optimal parameters of diameter,advance rate and strata reaction coefficient of pipe roof,the circumferential spacing is directly proportional to pipe roof deformation,it meets the requirement only if the length of pipe roof at the far end is not less than two times of the bench height in front of working face;(3)The sequences of controlling effect of vault settlement by adjusting pipe parameters are advance rate,strata mechanical behavior improvement by grouting,circumferential spacing,diameter and length in the order from good to bad.
引文
[1] SINGHB,VILADKARMN,SAMADHIYANK.ASemi-empiricalMethodfortheDesignofSupportSystemsinundergroundOpenings[J]. Tunnelling and Underground Space Technology, 1995, 10(3):375-383.
[2] GEOFF P. Ground Treatment[J]. World Tunnelling, 1996,(4):100-107.
[3] SATOH S, FURUYAMA S, MURAI Y. Construction of Subway Tunnel just beneath a Conventional Railway by Means of Large-di?ameter Long Pile-roof Method[C]//Proceedings of International Conference on North American Tunnelling, 1996:473-481.
[4] MUSSO G. Jacked Pipe Provides Roof for Underground Construction in Busy Urban Area[J]. ASCE, Civil Engineering, 1979, 49(11):79-82.
[5] MIWA M, OGASAWARA M. Tunneling through an Embankment Using All Ground Fasten Method[J]. Tunnelling and UndergroundSpace Technology, 2005, 20(2):121-127.
[6] YOO C S. Finite-element Analysis of Tunnel Face Reinforced by Longitudinal Pipes[J]. Computers and Geotechnics, 2002, 29(1):73-94.
[7] KOTAKE N, YMAMOTO Y, OKA K, et al. Design for Umbrella Method Based on Numerical Analyses and Field Measurements[J].International Journal of Rock Mechanics and Mining Science&Geomechanics Abstracts, 1995, 32(3):136A-136A.
[8]伍振志,傅志锋,王静,等.浅埋松软地层开挖中管棚注浆法的加固机理及效果分析[J].岩石力学与工程学报, 2005, 24(6):1025-1029.WU Zhenzhi, FU Zhifeng, WANG Jing, et al. Study of Support Mechanism and Effect of Shed-pipe Grouting Technology for Tunnel?ling Construction in Shallow-buried Soft Stratum[J]. Chinese Journal of Rock Mechanics and Engineering, 2005, 24(6):1025-1029.
[9]郭衍敬,房倩,李兵.浅埋暗挖地铁车站管棚的数值模拟及其加固效果分析[J].北京工业大学学报, 2010, 36(1):40-45.GUO Yanjing, FAGN Qian, LI Bing. Reinforcement Mechanism and Mechanical Analysis for Pipe Roof Support Used in Subway Sta?tion with Shallow Tunnel Construction Method[J]. Journal of Beijing University of Technology, 2010, 36(1):40-45.
[10]周顺华.软弱地层浅埋暗挖施工中管棚法的棚架原理[J].岩石力学与工程学报, 2005, 24(14):2565-2570.ZHOU Shunhua. Principles of Pipe Roof Applied to Shallow-buried Tunnels in Soft Ground[J]. Chinese Journal of Rock Mechanicsand Engineering, 2005, 24(14):2565-2570.
[11]董新平,周顺华,胡新朋.软弱地层管棚法施工中管棚作用空间分析[J].岩土工程学报,2006, 28(7):841-846.DONG Xinping, ZHOU Shunhua, HU Xinpeng. 3D Analysis of Function of Piperoof Applied in Soft Ground[J]. Chinese Journal ofGeotechnical Engineering, 2006, 28(7):841-846.
[12]贾金青,王海涛,涂兵雄,等.管棚力学行为的解析分析与现场测试[J].岩土力学, 2010,31(6):1858-1864.JIA Jinqing,WANG Haitao,TU Bingxiong,et al. Analytical Approach and Field Monitoring for Mechanical Behaviors of Pipe RoofReinforcement[J]. Rock and Soil Mechanics, 2010, 31(6):1858-1 864.
[13]郑俊杰,章荣军,杨庆年.浅埋隧道变基床系数下管棚的力学机制分析[J].岩土工程学报, 2009, 31(8):1165-1171.ZHENG Junjie, ZHANG Rongjun, YANG Qingnian. Mechanical Mechanism of Piperoofs with Variable Coefficient of Subgrade Re?action in Shallow Tunnels[J]. Chinese Journal of Geotechnical Engineering, 2009, 31(8):1165-1171.
[14]王道远,袁金秀,朱正国,等.水下盾构隧道纵向上浮理论解及工程应用[J].岩土力学, 2014, 35(11):3079-3085.WANG Daoyuan, YUAN Jinxiu, ZHU Zhengguo, et al. Theoretical Solution of Longitudinal Upward Movement of UnderwaterShield Tunnel and Its Application[J]. Rock and Soil Mechanics, 2014, 35(11):3079-3085.
[15]石钰锋.浅覆软弱围岩隧道超前预支护作用机理及工程应用研究[D].长沙:中南大学,2014.SHI Yufeng. Study on Mechanism and Engineering Application of Advanced Support for Lower Overburden Tunnel in Weak Stra?tum[D]. Changsha:Central South University, 2014.
[16]王道远,袁金秀,李俊,等.考虑施工特性的浅埋软弱洞口段管棚变形量预测及工程应用[J].岩石力学与工程学报, 2017,36(3):716-724.WANGDaoyuan,YUANJinxiu,LIJun,etal.DeformationPredictionofPipeRoofinShallowSoftPortalSectionofTunnelConsideringConstruction Feature[J]. Chinese Journal of Rock Mechanics and Engineering, 2017, 36(3):716-724.
[2] GEOFF P. Ground Treatment[J]. World Tunnelling, 1996,(4):100-107.
[3] SATOH S, FURUYAMA S, MURAI Y. Construction of Subway Tunnel just beneath a Conventional Railway by Means of Large-di?ameter Long Pile-roof Method[C]//Proceedings of International Conference on North American Tunnelling, 1996:473-481.
[4] MUSSO G. Jacked Pipe Provides Roof for Underground Construction in Busy Urban Area[J]. ASCE, Civil Engineering, 1979, 49(11):79-82.
[5] MIWA M, OGASAWARA M. Tunneling through an Embankment Using All Ground Fasten Method[J]. Tunnelling and UndergroundSpace Technology, 2005, 20(2):121-127.
[6] YOO C S. Finite-element Analysis of Tunnel Face Reinforced by Longitudinal Pipes[J]. Computers and Geotechnics, 2002, 29(1):73-94.
[7] KOTAKE N, YMAMOTO Y, OKA K, et al. Design for Umbrella Method Based on Numerical Analyses and Field Measurements[J].International Journal of Rock Mechanics and Mining Science&Geomechanics Abstracts, 1995, 32(3):136A-136A.
[8]伍振志,傅志锋,王静,等.浅埋松软地层开挖中管棚注浆法的加固机理及效果分析[J].岩石力学与工程学报, 2005, 24(6):1025-1029.WU Zhenzhi, FU Zhifeng, WANG Jing, et al. Study of Support Mechanism and Effect of Shed-pipe Grouting Technology for Tunnel?ling Construction in Shallow-buried Soft Stratum[J]. Chinese Journal of Rock Mechanics and Engineering, 2005, 24(6):1025-1029.
[9]郭衍敬,房倩,李兵.浅埋暗挖地铁车站管棚的数值模拟及其加固效果分析[J].北京工业大学学报, 2010, 36(1):40-45.GUO Yanjing, FAGN Qian, LI Bing. Reinforcement Mechanism and Mechanical Analysis for Pipe Roof Support Used in Subway Sta?tion with Shallow Tunnel Construction Method[J]. Journal of Beijing University of Technology, 2010, 36(1):40-45.
[10]周顺华.软弱地层浅埋暗挖施工中管棚法的棚架原理[J].岩石力学与工程学报, 2005, 24(14):2565-2570.ZHOU Shunhua. Principles of Pipe Roof Applied to Shallow-buried Tunnels in Soft Ground[J]. Chinese Journal of Rock Mechanicsand Engineering, 2005, 24(14):2565-2570.
[11]董新平,周顺华,胡新朋.软弱地层管棚法施工中管棚作用空间分析[J].岩土工程学报,2006, 28(7):841-846.DONG Xinping, ZHOU Shunhua, HU Xinpeng. 3D Analysis of Function of Piperoof Applied in Soft Ground[J]. Chinese Journal ofGeotechnical Engineering, 2006, 28(7):841-846.
[12]贾金青,王海涛,涂兵雄,等.管棚力学行为的解析分析与现场测试[J].岩土力学, 2010,31(6):1858-1864.JIA Jinqing,WANG Haitao,TU Bingxiong,et al. Analytical Approach and Field Monitoring for Mechanical Behaviors of Pipe RoofReinforcement[J]. Rock and Soil Mechanics, 2010, 31(6):1858-1 864.
[13]郑俊杰,章荣军,杨庆年.浅埋隧道变基床系数下管棚的力学机制分析[J].岩土工程学报, 2009, 31(8):1165-1171.ZHENG Junjie, ZHANG Rongjun, YANG Qingnian. Mechanical Mechanism of Piperoofs with Variable Coefficient of Subgrade Re?action in Shallow Tunnels[J]. Chinese Journal of Geotechnical Engineering, 2009, 31(8):1165-1171.
[14]王道远,袁金秀,朱正国,等.水下盾构隧道纵向上浮理论解及工程应用[J].岩土力学, 2014, 35(11):3079-3085.WANG Daoyuan, YUAN Jinxiu, ZHU Zhengguo, et al. Theoretical Solution of Longitudinal Upward Movement of UnderwaterShield Tunnel and Its Application[J]. Rock and Soil Mechanics, 2014, 35(11):3079-3085.
[15]石钰锋.浅覆软弱围岩隧道超前预支护作用机理及工程应用研究[D].长沙:中南大学,2014.SHI Yufeng. Study on Mechanism and Engineering Application of Advanced Support for Lower Overburden Tunnel in Weak Stra?tum[D]. Changsha:Central South University, 2014.
[16]王道远,袁金秀,李俊,等.考虑施工特性的浅埋软弱洞口段管棚变形量预测及工程应用[J].岩石力学与工程学报, 2017,36(3):716-724.WANGDaoyuan,YUANJinxiu,LIJun,etal.DeformationPredictionofPipeRoofinShallowSoftPortalSectionofTunnelConsideringConstruction Feature[J]. Chinese Journal of Rock Mechanics and Engineering, 2017, 36(3):716-724.