【作者】 关继发；

【导师】 李慧民；

【作者基本信息】 西安建筑科技大学 ， 土木工程建造与管理， 2008， 博士

【摘要】 在广泛查阅国内外相关文献的基础上,借鉴以往隧道穿越既有结构的工程风险管理经验,通过分析提炼、归纳总结,建立了一套新建地铁隧道穿越既有地铁的安全风险评估、管理体系,并完善了其配套的风险控制技术。该研究成果应用到北京地铁5号线下穿既有2号线区间隧道的工程实例中,取得了良好的安全、经济效益。(1)建立了隧道工程风险的评估体系,并探讨了隧道穿越既有地铁风险管理体系的内涵;基于风险动态分析方法,构建了隧道穿越既有地铁风险评估体系的基本流程图;明确了穿越既有地铁风险评估体系的研究思路和具体内容,并对穿越工程中的风险基础理论及风险控制关键技术进行了深入研究。(2)通过总结浅埋暗挖隧道穿越既有地铁工程中,安全风险产生的原因、风险影响因素,以及既有地铁的现状评估程序、安全风险等级划分、既有地铁接近度划分,确定既有地铁的安全风险评估的等级、范围和基本目标、内容。(3)提出了基于监测数据的动态风险分析方法。该方法非常适合于隧道工程的风险评估与管理,且很符合隧道工程的“动态设计、动态施工”的理念;它通过现场的实际勘察记录、勘测记录、施工监测数据,以及综合了地层的工程地质特征、隧道风险的动态因素、风险作用的环境因素等,来分析、跟踪、掌握工程风险动态特性,因而比常规的风险分析更具有主动性,也能对隧道工程中的风险进行更有效的管理和控制。(4)实践表明:对隧道穿越既有地铁实施动态的风险分析、评估、动态监测与控制后,工程风险能显著降低。特别是,施工管理、施工注浆及注浆抬升、支护及衬砌、隧道开挖等环节中,通过过程的风险动态控制,其工程风险水平、等级有明显降低,这说明在隧道穿越既有地铁施工过程中,实行动态风险跟踪、控制、评估,具有明显的风险防范效果。(5)确定了隧道风险控制指标及控制值。通过总结目前国外内风险评估指标体系所应遵循的原则,指出了广义风险评估指标及狭义评估指标之间的关系,完善了隧道施工风险控制指标的内涵,确定了隧道风险控制指标及控制值,指出了根据既有地铁的重要程度以及其产生危险的后果,应以技术性的控制指标为主,非技术性的控制指标为辅的思想。(6)地层变形理论研究与计算分析。通过分析新建隧道开挖产生地层变形—既有结构—轨道三者的相互作用关系,研究了既有结构和轨道的变形规律,以及二者之间可能发生的破坏类型和破坏模式。在穿越工程中,既可以根据施工方法,计算得到既有结构的安全控制标准;也可以根据既有结构的控制标准的反算,调整新建地铁隧道的施工方案,确保既有结构的安全。在施工过程中,及时进行风险评估、反馈,并对整个工程实行全过程控制,以确保工程安全。理论、计算分析同时揭示了既有地铁注浆抬升机理,并给出了抬升注浆的实施性参数,研究成果为以后类似工程提供了参考。在北京地铁5号线崇文门车站对穿越既有地铁工程实践中,文中研究成果应用良好,并得到了现场专家组的认可。(7)完善了穿越既有地铁的预警报警系统和抢险救援体系。组织了有效的风险分析、反馈、报警演练;通过调研分析及对既有地铁影响预测分析,对监控系统进行了选型与测试,使之能够实时掌握既有地铁结构和轨道系统的风险状态;制定了相应的变形风险控制措施和应急措施,根据监控数据的反馈和分析,及时采取措施或调整施工方案,确保了运营安全;并在目前铁路隧道三级管理的基础上,对每级管理进行了更加具体的细化,使得风险管理体系更易于运作。更多还原

【Abstract】 With development of society and economy,China transport construction develops rapidly in recent years and will boom for a long period.During the course of construction,severe accidents frequently happened in past years because of some subjective or objiective reasons which shocked all people.It is urgently required that risk management should be applied to the entire process of tunnel construction,in order to ensure workers,machinery and property are safe enough.It is no doubt that risk management will be popular and absolutely necessary in tunnel engineering.Based on broadly surveying the risk management documents at home and abroad, and making full use of successful engineering risk management experience of the new tunnel passing from the bottom of the existing subway in the past,By summing up and refining,risk evaluation and management has been set up,related key technologies being bettered.And the research results have been introduced to Beijing Metro 5 passing over exsited Metro 2,which have gained remarkable safty and profit fruits.(1) Building up a basic scientific research system for tunnel project,given connotative meaning of project risk management system when new tunnel passes over existing subway,given the basic process chart with the dynamic risk-based analysis of the new tunnel passing the existing subway.Cleared ideas and scope of study the new line passes from the bottom of the existing subway.Several key issues were brought forward about the basic theoretical study and risk control in tunnel engineering risk administration.(2) Summed up the reasons of arising risk security and their risk factors the new tunnel passes from the existing subway with the shallow mining tunnel method. Detailed analyzed the status assessment process of the existing line and the security risk rating before the new tunnel passing from the existing subway.The existing structure’s evaluation level Determining be determined by setting the scope and content of assessment.The levels evaluation can be determined to specific projects;the paper also refers to the contents and methods of the investigation and detection to the existing line(3) Analysis method that bases on monitoring data being on the basis of the theory of dynamic risk is the most appropriate method subtitling for risk assessment and management in tunnel construction,it is consistent with the tunnel project "dynamic design,construction dynamic" characteristics.The method comes into being by the actual site inspection records,according to monitoring data and the characteristics of the tunnel project,and surveying the dynamic risk factors,therefore it is more targeted than the conventional risk analysis method.It can greatly reflect real terms that risk dynamic changes with the tunnel construction process,and take an effective risk management and control in tunnel construction projects.(4) The application show that of dynamic risk analysis method based on monitoring data and risk assessment can dominantly reduce risk in the tunnel passing over existing metro.Especilly,construction management,grouting construction,strata lifting with grouting method,tunnel supporting,lining construction and tunnel excavating has changed in the process of dynamic control,such as level of risk has reduced from the original fifth or fourth to fourth or third.The above shows that the dynamic risk tracking and control can effectively reduce the construction risk when the tunnel passes from the existing line,which has obvious benefits to the risk prevention.(5) Summed up the current risk assessment system to be followed the principle in home and abroad,indicated the relationship between broad and narrow risk assessment’s index.The meaning of the risk control in tunnel construction is improved. Summed up tunnel risk control indexes and control values.According to the existing line and its importance to society after a risk of causing economic losses and social implications should follow the idea the technical control is main,non-technical as a supplement.(6) I gained several key technologies of the risk control in the tunnel passing from the existing line,the achievements show below:1) Based on former study,the key problem:interaction and control target: engineering safety for new subway passing from the bottom of the existing line is studied.According to different aims in different construction stages,5 main technical points are summarized and technical system for such passing project is formed.In this thesis studies are carried out respectively for each different technical points.2) The magnitude of displacement in each construction step is analyzed using energy method.Settlement control standards of each construction step for the existing line is made.According to the characters of the new line and operation requirements for the existing line,monitoring measures are formed.These analyses and feed back measures are made to ensure the safety of existing structure.3) Grouting used in subway for existing line lifting up is studied.The research of grouting parameter and grouting method can offer guidance to this kind of project.(7) Trying to build an alarming and rescue system when tunnel passing over the existing metro.Effective analysis,feedback and alarming system has been organized and drilled successfully.Through researching and analyzing the impact to existing line and prediction analysis,monitoring systems have been studied and chosen to enable it to real-time control the state of the subway structure and the track system.Formulated the corresponding deformation control measures and emergency measures,according to the monitoring feedback and analysis,and take timely measures or adjust the construction scheme to ensure the operational safety,And,I make a more detailed refinement on the basis of the current three-level management of the rail tunnel,which is convenient to operate and practise.更多还原