城区大断面小净距隧道洞口施工关键技术研究

发布时间：2018-05-21 11:15

本文选题：小净距 + 洞口　；参考：《山东建筑大学》2015年硕士论文

【摘要】：山区城市修建隧道可以克服地形条件限制,有利于城市交通发展,但是城区隧道洞口段一般位于浅埋地带,洞口覆盖层相对比较薄,围岩破碎且夹有土层,地表土层甚至为杂填土。在此种围岩条件下大断面小净距隧道洞口段存在以下问题：临时边坡和仰坡容易失稳破坏、围岩不能靠自身的稳定性成拱和加固措施的选择等。针对以上问题,本文依托济南市石方峪隧道工程,主要研究工作有以下几个方面：(1)研究洞口边坡的稳定性影响因素和破坏模式,针对边坡破坏形式,总结边坡处治的方案；并利用刚体极限平衡法计算边坡的安全系数随土力学参数的变化改变情况,研究确保隧道洞口长大边坡稳定的加固方案。(2)根据石方峪隧道工程地质特点和施工难点,研究分析石方峪隧道边坡、仰坡隐患及病害控制：①洞口高陡边坡的加固措施,研究边坡开挖过程中的稳定性：②仰坡开裂病害,分析仰坡病害的成因与治理措施。(3)利用有限元MIDAS GTS模拟计算采用小净距隧道中隔壁法和三台阶七步开挖法的位移沉降和塑性区范围,选择适合城区浅埋隧道进洞开挖的施工方法,并根据模拟工况选择加固方案。(4)通过在石方峪隧道的监控量测,获取施工过程中的围岩和支护体系的变化信息；分析洞口段监控量测数据,判断石方峪隧道开挖过程中需要重点监控的时段,及时反馈分析。目前石方峪隧道工程已经竣工,本文提出的关于石方峪隧道的施工方法和加固措施是合理的,取得了显著的工程效果。
[Abstract]:The construction of tunnel in mountainous cities can overcome the limitation of topographic conditions and is beneficial to the development of urban traffic. However, the tunnel entrance section of urban tunnel is generally located in the shallow buried zone, with relatively thin overburden at the entrance of the tunnel, the surrounding rock is broken and there are soil layers in it. The surface soil layer is even mixed fill. Under the condition of this kind of surrounding rock, the following problems exist in large section and small clear distance tunnel entrance section: temporary slope and upside-slope are vulnerable to instability and failure, the surrounding rock can not be arched by its own stability and the choice of reinforcement measures, and so on. In view of the above problems, this paper relies on the Shifangyu tunnel project of Jinan city, the main research work has the following several aspects: 1) study the influence factor and the failure mode of the slope stability of the portal slope, summarizes the slope treatment plan in view of the slope failure form; And using rigid body limit equilibrium method to calculate the change of slope safety coefficient with soil mechanics parameters, and to study the reinforcement scheme to ensure the stability of long slope at tunnel entrance.) according to the engineering geological characteristics and construction difficulties of Shifangyu tunnel, The study and Analysis of the Slope of Shifangyu Tunnel, the hidden trouble and the disease control of the vertical slope, the reinforcement measures of the high and steep slope at the entrance of the Wei 1 tunnel, the stability of the slope during the excavation of the tunnel and the cracking disease of the upside-slope, Analysis of the causes and treatment measures of the disease of upside-slope. (3) using finite element MIDAS GTS to simulate and calculate the displacement settlement and plastic zone of the tunnel with small clear distance and three steps and seven steps excavation method. The construction method suitable for excavation of shallow buried tunnel in urban area is selected. According to the simulated working condition, the reinforcement scheme is selected. Through monitoring and measuring in Shifangyu tunnel, the change information of surrounding rock and supporting system in the construction process is obtained. The monitoring data of Dongkou section are analyzed, and the time period of key monitoring during excavation of Shifangyu tunnel is judged, and the timely feedback analysis is carried out. At present, Shifangyu tunnel project has been completed. The construction method and reinforcement measures of Shifangyu tunnel proposed in this paper are reasonable and have achieved remarkable engineering effect.
【学位授予单位】：山东建筑大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U455.4

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