【作者】 杨广武；

【导师】 施仲衡；

【作者基本信息】 北京交通大学 ， 道路与铁道工程， 2010， 博士

【摘要】 随着我国城市轨道交通线网的大规模建设,必然会遇到线路之间的相互交叉、穿越的工程问题。这些穿越问题直接关系到既有地铁线路的正常运营、在建工程的施工安全、工期和工程造价,对地铁建设和发展提出了新的挑战。我国的北京、上海等地及国外城市在地铁建设过程中遇到的地下工程穿越既有地铁线路的问题虽然已有成功的案例,但尚未形成综合技术体系,没有提出完善的变形控制标准,而且花费的成本和代价也值得研究。本文在总结已有工程经验和研究成果的基础上,结合典型工程——北京市城市轨道交通首都机场线东直门站C区上(下)穿越既有城铁13号线东直门站站后折返线工程,对地下工程穿越既有地铁线问题开展系统研究(包括穿越工程分类、变形控制的指标体系及其限值、控制标准制定原则及方法、穿越工程顶升控制技术、施工过程中的监测与信息反馈、工后评估等),取得了以下几个方面的成果：(1)对地下工程穿越既有地铁线路的国内外典型案例进行了分析,对工程案例分类及其特征进行了研究。(2)对穿越工程中既有地铁线路变形的相关影响因素进行了分析,在此基础上提出了穿越工程变形控制的指标体系。(3)既有线的变形控制标准包括隧道结构变形控制标准和轨道结构变形控制标准。轨道结构变形控制标准的制定应以利于养护维护、维修可用为原则。隧道结构变形控制标准的确定主要涉及到既有线的现状承载力和施工对既有线影响程度两方面的因素。对于二者的确定,必须经过完整的计算分析,取其中的小者作为隧道结构变形的控制标准,且隧道结构变形控制标准必须服从于轨道结构变形控制的要求。控制标准制定应采用“分区、分级、分阶段”的原则,以利于实施和控制。(4)同步顶升技术是一种积极的主动防御变形控制措施,按“分区、分阶段、分组、分级”的原则确定顶升方案是有效的,顶升控制的核心是“因势利导”,按照既有结构的变形现状,动态调整千斤顶布置和顶力分布,以达到控制既有结构变形发展的效果。采取设防脱护轨等措施增强轨道自身抵抗变形的能力,结合监控量测,对轨道进行分级防护,并配之以相应的线路调整方法、道床开裂和道床与结构脱离整治方法,是确保既有线路安全运营的应急之策,应超前规划。(5)穿越工程应采用自动化监测与人工监测相结合的综合监测形式,对既有地铁进行实时监测,有效地保障施工及运营安全。而建立高效、便捷的信息反馈流程和体系对于穿越工程施工至关重要。监测数据表明,折返线基本经历了“上浮～下沉～趋于稳定～稳定”的变形过程。隧道结构、轨道结构测点累计变形量最终基本控制在13.5mm之内,实现了原设计控制目标,表明顶升控制技术可以有效的控制变形。更多还原

【Abstract】 As the urban rail transit networks of China are built at a large scale, crossing project between different lines becomes inevitably. These crossing projects are directly related to the operation safety, construction safety of under construction project, constructing period and cost of the metro lines, and cast new challenge on the construction and development of metro. Although there have been some successful cases of new-built metro lines crossing existing metro lines encountered during the metro construction in Beijing, Shanghai and other cities abroad, integrated technical system has not been formed, and sophisticated deformation controlling standard has not been achieved, furthermore, the price of existing crossing measurements are worthy of studying.Based on the summarization of former engineering experience and achievement, in combination of classical crossing case, International Airport Line of Beijing Urban Rail Transit under (upward) crossing the behind-station turn back line of existing metro line, urban rail 13th, this dissertation systemically studies the problem of underground projects crossing existing metro line, and attained the following results.(1) Domestic and abroad classical cases of underground projects crossing existing metro lines are analyzed, and the classification and characteristics of these projects are studied.(2) The related factors influencing the deformation of existing metro lines in crossing engineering are analyzed, based on which the characterization value of deformation controlling code are proposed.(3) Deformation controlling code of existing lines, including tunnel structure deformation controlling and track structure deformation controlling standard are put forward. The establishment of track structure deformation controlling standard should follow the principle of being beneficial to maintenance. The confirmation of tunnel structure deformation controlling standard is mainly involved with two factors, the present bearing capacity of existing structure and the impact of construction on existing line. In regard of confirmation of these two factors, complete computing and analysis are prerequisite, and the smaller one can be taken as the tunnel structure deformation controlling standard. And also the tunnel deformation controlling standard must give way to the track structure deformation controlling requirement. To be beneficial to implementation and control, using of controlling standard should follow the principle of considering different areas, classes and stages.(4) Synchronous lift-up technique is a kind of active controlling measure, and it is effective of making lift-up plan that following the principle of considering different areas, stages, groups and classes. The core of lift-up controlling is improving the occasion, which means dynamic adjusting the collocation and distribution of jack according to the deformation situation of existing lines. Taking guardrail, combining monitoring and line adjustment methods, are lash-up method of making sure the safety of existing line operation.(5) In order to ensure construction and operation safety, automatic and artificial monitoring should be taken in crossing projects. It is important to establish the information feed-back system. Monitoring data indicates that the deformation process is floating-subsidence-tending to stabilization-stabilization. The accumulative total deformation of tunnel structure and track structure is within 13.5mm, which indicates that lift-up controlling technique can control deformation effectively.更多还原