新奥法施工数值模拟及量测研究
摘要
随着我国城市化的快速进展,地下空间的开发与利用也已经提高到人类发展的战略高度。城市地铁极大的缓解了城市交通阻塞、空气污染、生存空间等危机。作为常用的一种施工方法新奥法(NATM)，是以维护和利用围岩的自稳能力为基点,应用岩体力学原理,将锚杆和喷射混凝土集合在一起作为主要支护手段,形成以锚杆、喷射混凝土和隧道围岩三位一体的承载结构。
由于隧道施工不可避免的会产生岩土体扰动,引起隧道周边岩土体的移动与变形。目前国内外不少学者已对此问题作了大量深入的研究。本文结合大连地铁一期工程215标段隧道新奥法施工量测,采用大型有限元软件ABAQUS对开挖、初支进行了模拟。本文的主要研究内容及结论：
(1)归纳了国内外隧道变形研究现状,总结了新奥法施工工艺、量测技术及大连地铁215标段施工概况和监测项目并简单介绍了盾构法。
(2)通过六心圆法双洞施工模拟可以得到,变形量主要集中在上断面开挖过程中。当两洞之间间距大于2B(隧洞的开挖宽度)时,可忽略两洞之间的施工影响。上断面开挖完毕后,拱脚处会产生较大的集中应力,底部土体产生较大隆起,应及时施作仰拱,锁脚锚杆可以有效减小集中应力。净空收敛最大变形量发生在拱脚。
(3)对同一断面不同开挖支护方式进行模拟和不同围岩的安全系数进行模拟,得出超前小导管支护更适合软岩。双线隧道地表沉降槽曲线为“双峰”形态,隧道埋深大于>3D(D为隧道直径)时,不再必要量测地表隆沉。
(4)对同一断面采用不同的开挖进尺进行三维数值模拟,发现在衬砌的拱顶和拱底,地层变形量最大,随着与隧道工作面距离的加大,变形量逐渐减小,具有衰减性。当隧道工作面向前延伸到5倍的开挖进尺时,初始工作面由急剧变形阶段转为缓慢变形阶段。进尺大小对地层的变形影响较大。
(5)通过对不同厚度衬砌模拟发现衬砌并非越厚越好,存在一合理值。锚杆的主要承载能力主要集中于锚杆的前段。通过释放围岩不同应力推断由于围岩的自承能力,初期支护存在一个较合理的时间段。塑性区主要分布在边墙,应力和弯矩也是边墙最大。
(6)选择本标段埋置较深、较浅、地质较差3处断面进行了二维模拟及里程为DK35+710处断面进行了三维模拟,模拟值和现场监控量测数据得到了较好的一致性。
With the rapid development of urbanization in China, the development and utilization of underground space also has been increased to the strategic height of human development. Urban subway greatly eases the traffic congestion in cities, air pollution, living space and crisis. The NATM, as a common construction method, based on Rock Mechanics Principle and utilized the self-stability of surrounding rock, holds bolt and shotcrete together as support, and therefore forms a trinity bearing structure composed of bolt, shotcrete and tunnel surrounding rock.
Tunnel engineering construction disturbs the stratum inevitably, and generates deformation and movement around. Currently, many domestic and foreign scholars have made a lot of further research about this problem. The large finite element analytic software ABAQUS is adopted to have a simulation on the construction of excavation and primary support based on the first stage construction of215-section of Dalian Metro. The main research contents and conclusion are as follows:
(1) The paper concludes the tunnel deformation research situation at home and abroad, summarizes the new Austrian law construction process,measurement technology and construction and monitoring project of the Dalian subway section of215,the paper also introduces the shield law simpily.
(2) Through six heart circle of the double hole construction simulation, deformation mainly concentrates in the up section excavation process. When space between two lines was greater than2B (tunnel excavation width), can ignore the influence between construction. After the completion of the excavation, arch feet will produce larger concentration of stress, and the bottom soil produces larger uplift, so Yang arch should be timely done, feet-lock bolt can effectively reduce the stress concentration. The maximum deformation of headroom convergence occurs in the arch feet.
(3)The same section of different excavation supporting method simulation and different rock mass of the safety factor method simulation advance that small catheter support more suitable for soft rock. Two-lane tunnel surface subsidence curve of groove "twin peaks" form. Tunnel buried greater than>3D (D for tunnel diameter) will no longer necessary to measure the surface deformation.
(4)3D numerical simulation is used in the same cross-section, at the up and down of lining, the stratum deformation reaches maximum, and it decreases along with the distance to the working face increased. The deformation of initial working surface transforms from the sharp deformation stage to slow deformation stage when the excavation face extended forward five excavation steps and the deformation mainly happens at the excavation of the up stage.
(5) Through simulation on different thick lining show that lining find that lining not the thicker the better and there is a reasonable value. The main carrying capacity mainly focus on the anchor front-end. Through the release of surrounding rock stress shows that because of the different bearing ability, there is a more reasonable time for primary support. The plastic zone is mainly distributed in the wall, stress and bending moment is also the biggest in the wall.
(6) It is adopted to build a2D numerical simulation at the period of excavation and the initial support in three cross-sections located in the deeper, the shallower and the geological poorer area, and a3D simulation of DK35+710section based on the first stage construction of215-section of Dalian Metro. Simulation value and site monitoring data obtain better consistency.
由于隧道施工不可避免的会产生岩土体扰动,引起隧道周边岩土体的移动与变形。目前国内外不少学者已对此问题作了大量深入的研究。本文结合大连地铁一期工程215标段隧道新奥法施工量测,采用大型有限元软件ABAQUS对开挖、初支进行了模拟。本文的主要研究内容及结论：
(1)归纳了国内外隧道变形研究现状,总结了新奥法施工工艺、量测技术及大连地铁215标段施工概况和监测项目并简单介绍了盾构法。
(2)通过六心圆法双洞施工模拟可以得到,变形量主要集中在上断面开挖过程中。当两洞之间间距大于2B(隧洞的开挖宽度)时,可忽略两洞之间的施工影响。上断面开挖完毕后,拱脚处会产生较大的集中应力,底部土体产生较大隆起,应及时施作仰拱,锁脚锚杆可以有效减小集中应力。净空收敛最大变形量发生在拱脚。
(3)对同一断面不同开挖支护方式进行模拟和不同围岩的安全系数进行模拟,得出超前小导管支护更适合软岩。双线隧道地表沉降槽曲线为“双峰”形态,隧道埋深大于>3D(D为隧道直径)时,不再必要量测地表隆沉。
(4)对同一断面采用不同的开挖进尺进行三维数值模拟,发现在衬砌的拱顶和拱底,地层变形量最大,随着与隧道工作面距离的加大,变形量逐渐减小,具有衰减性。当隧道工作面向前延伸到5倍的开挖进尺时,初始工作面由急剧变形阶段转为缓慢变形阶段。进尺大小对地层的变形影响较大。
(5)通过对不同厚度衬砌模拟发现衬砌并非越厚越好,存在一合理值。锚杆的主要承载能力主要集中于锚杆的前段。通过释放围岩不同应力推断由于围岩的自承能力,初期支护存在一个较合理的时间段。塑性区主要分布在边墙,应力和弯矩也是边墙最大。
(6)选择本标段埋置较深、较浅、地质较差3处断面进行了二维模拟及里程为DK35+710处断面进行了三维模拟,模拟值和现场监控量测数据得到了较好的一致性。
With the rapid development of urbanization in China, the development and utilization of underground space also has been increased to the strategic height of human development. Urban subway greatly eases the traffic congestion in cities, air pollution, living space and crisis. The NATM, as a common construction method, based on Rock Mechanics Principle and utilized the self-stability of surrounding rock, holds bolt and shotcrete together as support, and therefore forms a trinity bearing structure composed of bolt, shotcrete and tunnel surrounding rock.
Tunnel engineering construction disturbs the stratum inevitably, and generates deformation and movement around. Currently, many domestic and foreign scholars have made a lot of further research about this problem. The large finite element analytic software ABAQUS is adopted to have a simulation on the construction of excavation and primary support based on the first stage construction of215-section of Dalian Metro. The main research contents and conclusion are as follows:
(1) The paper concludes the tunnel deformation research situation at home and abroad, summarizes the new Austrian law construction process,measurement technology and construction and monitoring project of the Dalian subway section of215,the paper also introduces the shield law simpily.
(2) Through six heart circle of the double hole construction simulation, deformation mainly concentrates in the up section excavation process. When space between two lines was greater than2B (tunnel excavation width), can ignore the influence between construction. After the completion of the excavation, arch feet will produce larger concentration of stress, and the bottom soil produces larger uplift, so Yang arch should be timely done, feet-lock bolt can effectively reduce the stress concentration. The maximum deformation of headroom convergence occurs in the arch feet.
(3)The same section of different excavation supporting method simulation and different rock mass of the safety factor method simulation advance that small catheter support more suitable for soft rock. Two-lane tunnel surface subsidence curve of groove "twin peaks" form. Tunnel buried greater than>3D (D for tunnel diameter) will no longer necessary to measure the surface deformation.
(4)3D numerical simulation is used in the same cross-section, at the up and down of lining, the stratum deformation reaches maximum, and it decreases along with the distance to the working face increased. The deformation of initial working surface transforms from the sharp deformation stage to slow deformation stage when the excavation face extended forward five excavation steps and the deformation mainly happens at the excavation of the up stage.
(5) Through simulation on different thick lining show that lining find that lining not the thicker the better and there is a reasonable value. The main carrying capacity mainly focus on the anchor front-end. Through the release of surrounding rock stress shows that because of the different bearing ability, there is a more reasonable time for primary support. The plastic zone is mainly distributed in the wall, stress and bending moment is also the biggest in the wall.
(6) It is adopted to build a2D numerical simulation at the period of excavation and the initial support in three cross-sections located in the deeper, the shallower and the geological poorer area, and a3D simulation of DK35+710section based on the first stage construction of215-section of Dalian Metro. Simulation value and site monitoring data obtain better consistency.
引文
[1]黄宏伟,张冬梅.盾构隧道施工引起的地表沉降及现场监控[J].岩石力学与工程学报,2001,20(增)：1814-1820.
[2]Peck R B. Tunneling in soils [J]. In:10th ICSMFE[C]. Stockholm.1981:607-628.
[3]Attewell P B. Engineering contract,site investigation and surface movements in tunnelling works [J]. In:Balkema A A. Softground tunnelling 2 failures and displacement [C]. Rotterdam.1981:5-12.
[4]Attewell P B. Woodman J P. Predicting the Dynamics of Ground Settlement and its Derivatives Caused by Tunneling in soil[J]. Ground Engineering, 1982,15(8):13-20,36.
[5]朱忠隆,张庆贺,易宏传.软土隧道纵向地表沉降的随机预测方法[J].岩土力学,2001,22(1)：56-59.
[6]施成华,彭立敏,刘宝琛.浅埋隧道开挖对地表建筑物的影响[J].岩土力学与工程学报,2004,23(19)：3310-3316.
[7]许江,顾义磊,康骥鸣.隧道与地表构筑物相互影响的研究[J].岩土力学2005,26(6)：889-892.
[8]卿伟宸,廖红建,钱春宇.地下隧道施工对相邻建筑物及地表的沉降的影响[J].地下空间与工程学报,2005,1(6)：960-963.
[9]李强,王明年,李德才等.地铁车站暗挖隧道施工对既有桩基的影响[J].岩石力学与工程学报,2006,25(1)：184-190.
[10]吴波,高波.地铁区间隧道施工对邻近管线的影响研究[J].岩土力学学报,2002,21(增2)：2451-2456.
[11]陈先国,高波.地铁近距离平行隧道有限元数值模拟[J].岩石力学与工程学报,2002,21(9)：1330-1334.
[12]朱泽兵.大跨超浅埋轻轨车站隧道控制技术研究[D].重庆：重庆大学土木工程学院,2010.
[13]董呈龙.基于监控量测和数值模拟的隧道围岩参数反演分析[D].武汉：武汉理工大学土木工程与建筑学院,2009.
[14]赵星光.地下工程岩体剪胀与锚杆支护的相互影响[J].岩石力学与工程学报,2010(10)：2056-2061.
[15]侯朝炯,郭励生,勾攀峰.煤巷锚杆支护[M].徐州：中国矿业大学出版社,1999.
[16]孙钧,周健,龚晓南等.受施工扰动影响土体环境稳定理论与变形控制[J].同济大学学报(自然科学版),2004,32(10)：1261-1269.
[17]刘自强.泸沽湖机场岩溶发育特征及地基稳定性分析与评价[D].成都：成都理工大学土木建筑学院,2011.6.
[18]铁道科学院等.铁路隧道复合衬砌研究总报告[R].鉴定报告,1986.
[19]铁道科学院西南所等.特浅埋软弱围岩隧道的修建技术[R].鉴定报告,1984.
[20]许燕峰,苏钧.浅埋暗挖法隧道施工引起地面沉降的原因及控制措施[J].世界隧道,1998,3：49-52.
[21]Katzenbaeh, R. andH. breth. (1881). Non-linear3-nanalysisforN-TMinFran-rtelayproe.1 othInt Conf5011MechFound Eng. Stockholm. Vol.1,315-318.
[22]朱剑锋.考虑扰动影响的土体性状研究[D].杭州：浙江大学工程学院,2011.
[23]HardinB.O., DmeviehV. P. ShearModulusandDamPingin50115:Measurementand ParallleterEffeets[J]. Joumalof5011MechaniesandFoundationDivision, ASCE,1972, 98(6):603-624.
[24]RutledgeP. C. RelationofUndisturbedSamPlingtoLaboratoryTest[J]. Joumalof TransPortationEngineering, ASCE,1994,109:1155-1183.
[25]童雷.软土浅埋隧道变形、渗流及固结性状研究[D].杭州：浙江大学工程学院,2010.
[26]孔恒.城市地铁隧道浅埋暗挖法地层预加固机理及其应用研究[D].北京：北方交通大学大学土木工程学院,2003.
[27]任长吉.公路隧道围岩稳定性分析及支护对策研究[D].吉林：吉林大学建设工程学院,2008.
[28]施成华,彭立敏,雷明锋.浅埋隧道施工地层变形时空统一与此理论与应用[M].北京：科学出版社,2010.9.
[29][32][33]李晓红.隧道奥法及其量测技术[M].北京：科学出版社,2001.
[30]彭立敏,刘小兵.隧道工程[M].长沙：中南大学出版社,2009.
[31]《大连市轨道交通Ⅰ期215标卫生中心至体育中心车站施工图纸》[R],2009.
[34]中交第一公路工程局有限公司.JTG F60-2009公路隧道施工技术规范[S].2009.
[35]铁道部.TB10121-2007铁路隧道监控量测技术规程[S].2007.
[36]《大连市轨道交通Ⅰ期215标后革-卫生中心站区间隧道暗挖段施工方案》[R],2010.
[37]《大连市轨道交通Ⅰ期215标卫生中心站-体育中心站区间隧道暗挖段施工方案》[R],2010.
[38]《大连市轨道交通Ⅰ期215标后革-卫生中心站区间隧道暗挖段监测方案》[R],2010.
[39]《大连市轨道交通Ⅰ期215标卫生中心站-体育中心站区间隧道暗挖段监测方案》[R],2010.
[40]彭立敏,刘小兵.隧道工程[M].长沙：中南大学出版社,1991.
[41]刘建航,侯学渊.盾构法隧道[M].北京：中国铁道出版社,1991.
[42]石亦平,周玉蓉ABAQUS有限元分析实例详解[M].北京：机械工业出版社,2006.
[43]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,1991.
[44]郑永学,矿山岩体力学[M].北京：冶金工业出版社,1995.
[45]朱训国.杨庆.栾茂田.用ABAQUS模拟NATM隧道施工过程[J].岩士力学2006(27)(增刊)234-249.
[46]易立.大跨隧道施工方法选择的敏感性分析[D].重庆：重庆大学土木工程与力学学院,2005.
[47]罗清明,李亮,杨小礼.软岩隧道的围岩变形计算[J].长沙铁道学院学报,2003,21(2)：14-18.
[48]《大连地铁二号线卫生中心站至体育中心站区间岩土工程勘察报告》[R],2009.
[49]《大连地铁二号线后革站至卫生中心站区间岩土工程勘察报告》[R],2009.
[50]GB50218—94,工程岩土分级标准及条文说明[S].
[51]Manzari MT, Nour M A. Signifieanee of soil dilataney in slope stability analysis[J]. Journal of Geoteehnical and Geoenvironmental Engineering, ASCE,2000, 126(1):75 - 80.
[52]马晓雨.基于强度折减有限元法的土坡稳定性分析研究[D].大连,大连理工大学土木水利学院,2008.
[53]王峥峥.跨断层隧道结构非线性地震损伤反应分析[D].成都：西南交通大学土木工程学院,2007.
[54]童磊.软土浅埋隧道变形、渗流及固结性状研究[D].杭州：浙江大学建筑工程学院,2010.
[2]Peck R B. Tunneling in soils [J]. In:10th ICSMFE[C]. Stockholm.1981:607-628.
[3]Attewell P B. Engineering contract,site investigation and surface movements in tunnelling works [J]. In:Balkema A A. Softground tunnelling 2 failures and displacement [C]. Rotterdam.1981:5-12.
[4]Attewell P B. Woodman J P. Predicting the Dynamics of Ground Settlement and its Derivatives Caused by Tunneling in soil[J]. Ground Engineering, 1982,15(8):13-20,36.
[5]朱忠隆,张庆贺,易宏传.软土隧道纵向地表沉降的随机预测方法[J].岩土力学,2001,22(1)：56-59.
[6]施成华,彭立敏,刘宝琛.浅埋隧道开挖对地表建筑物的影响[J].岩土力学与工程学报,2004,23(19)：3310-3316.
[7]许江,顾义磊,康骥鸣.隧道与地表构筑物相互影响的研究[J].岩土力学2005,26(6)：889-892.
[8]卿伟宸,廖红建,钱春宇.地下隧道施工对相邻建筑物及地表的沉降的影响[J].地下空间与工程学报,2005,1(6)：960-963.
[9]李强,王明年,李德才等.地铁车站暗挖隧道施工对既有桩基的影响[J].岩石力学与工程学报,2006,25(1)：184-190.
[10]吴波,高波.地铁区间隧道施工对邻近管线的影响研究[J].岩土力学学报,2002,21(增2)：2451-2456.
[11]陈先国,高波.地铁近距离平行隧道有限元数值模拟[J].岩石力学与工程学报,2002,21(9)：1330-1334.
[12]朱泽兵.大跨超浅埋轻轨车站隧道控制技术研究[D].重庆：重庆大学土木工程学院,2010.
[13]董呈龙.基于监控量测和数值模拟的隧道围岩参数反演分析[D].武汉：武汉理工大学土木工程与建筑学院,2009.
[14]赵星光.地下工程岩体剪胀与锚杆支护的相互影响[J].岩石力学与工程学报,2010(10)：2056-2061.
[15]侯朝炯,郭励生,勾攀峰.煤巷锚杆支护[M].徐州：中国矿业大学出版社,1999.
[16]孙钧,周健,龚晓南等.受施工扰动影响土体环境稳定理论与变形控制[J].同济大学学报(自然科学版),2004,32(10)：1261-1269.
[17]刘自强.泸沽湖机场岩溶发育特征及地基稳定性分析与评价[D].成都：成都理工大学土木建筑学院,2011.6.
[18]铁道科学院等.铁路隧道复合衬砌研究总报告[R].鉴定报告,1986.
[19]铁道科学院西南所等.特浅埋软弱围岩隧道的修建技术[R].鉴定报告,1984.
[20]许燕峰,苏钧.浅埋暗挖法隧道施工引起地面沉降的原因及控制措施[J].世界隧道,1998,3：49-52.
[21]Katzenbaeh, R. andH. breth. (1881). Non-linear3-nanalysisforN-TMinFran-rtelayproe.1 othInt Conf5011MechFound Eng. Stockholm. Vol.1,315-318.
[22]朱剑锋.考虑扰动影响的土体性状研究[D].杭州：浙江大学工程学院,2011.
[23]HardinB.O., DmeviehV. P. ShearModulusandDamPingin50115:Measurementand ParallleterEffeets[J]. Joumalof5011MechaniesandFoundationDivision, ASCE,1972, 98(6):603-624.
[24]RutledgeP. C. RelationofUndisturbedSamPlingtoLaboratoryTest[J]. Joumalof TransPortationEngineering, ASCE,1994,109:1155-1183.
[25]童雷.软土浅埋隧道变形、渗流及固结性状研究[D].杭州：浙江大学工程学院,2010.
[26]孔恒.城市地铁隧道浅埋暗挖法地层预加固机理及其应用研究[D].北京：北方交通大学大学土木工程学院,2003.
[27]任长吉.公路隧道围岩稳定性分析及支护对策研究[D].吉林：吉林大学建设工程学院,2008.
[28]施成华,彭立敏,雷明锋.浅埋隧道施工地层变形时空统一与此理论与应用[M].北京：科学出版社,2010.9.
[29][32][33]李晓红.隧道奥法及其量测技术[M].北京：科学出版社,2001.
[30]彭立敏,刘小兵.隧道工程[M].长沙：中南大学出版社,2009.
[31]《大连市轨道交通Ⅰ期215标卫生中心至体育中心车站施工图纸》[R],2009.
[34]中交第一公路工程局有限公司.JTG F60-2009公路隧道施工技术规范[S].2009.
[35]铁道部.TB10121-2007铁路隧道监控量测技术规程[S].2007.
[36]《大连市轨道交通Ⅰ期215标后革-卫生中心站区间隧道暗挖段施工方案》[R],2010.
[37]《大连市轨道交通Ⅰ期215标卫生中心站-体育中心站区间隧道暗挖段施工方案》[R],2010.
[38]《大连市轨道交通Ⅰ期215标后革-卫生中心站区间隧道暗挖段监测方案》[R],2010.
[39]《大连市轨道交通Ⅰ期215标卫生中心站-体育中心站区间隧道暗挖段监测方案》[R],2010.
[40]彭立敏,刘小兵.隧道工程[M].长沙：中南大学出版社,1991.
[41]刘建航,侯学渊.盾构法隧道[M].北京：中国铁道出版社,1991.
[42]石亦平,周玉蓉ABAQUS有限元分析实例详解[M].北京：机械工业出版社,2006.
[43]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,1991.
[44]郑永学,矿山岩体力学[M].北京：冶金工业出版社,1995.
[45]朱训国.杨庆.栾茂田.用ABAQUS模拟NATM隧道施工过程[J].岩士力学2006(27)(增刊)234-249.
[46]易立.大跨隧道施工方法选择的敏感性分析[D].重庆：重庆大学土木工程与力学学院,2005.
[47]罗清明,李亮,杨小礼.软岩隧道的围岩变形计算[J].长沙铁道学院学报,2003,21(2)：14-18.
[48]《大连地铁二号线卫生中心站至体育中心站区间岩土工程勘察报告》[R],2009.
[49]《大连地铁二号线后革站至卫生中心站区间岩土工程勘察报告》[R],2009.
[50]GB50218—94,工程岩土分级标准及条文说明[S].
[51]Manzari MT, Nour M A. Signifieanee of soil dilataney in slope stability analysis[J]. Journal of Geoteehnical and Geoenvironmental Engineering, ASCE,2000, 126(1):75 - 80.
[52]马晓雨.基于强度折减有限元法的土坡稳定性分析研究[D].大连,大连理工大学土木水利学院,2008.
[53]王峥峥.跨断层隧道结构非线性地震损伤反应分析[D].成都：西南交通大学土木工程学院,2007.
[54]童磊.软土浅埋隧道变形、渗流及固结性状研究[D].杭州：浙江大学建筑工程学院,2010.