新建隧道施工对既有隧道的安全风险评估研究

发布时间：2018-06-11 13:59

  本文选题：新建隧道 + 台阶法　； 参考：《重庆交通大学》2015年硕士论文

【摘要】：近年来,我国经济的腾飞伴随着交通行业的发展,国家越来越重视基础设施建设,在路桥隧方面投入了大量资金。20世纪以来,汽车运输量不断增加,公路路线标准相应提高,公路隧道也逐渐增多。在此背景下,由于隧道受许多因素影响,隧道大量的修建,但有时隧道修建受地质、地形及空间的限制,出现了许多在已修建完成的隧道附近新建隧道即建设既有隧道的复线、新建铁路隧道与既有铁路隧道并行、一次性建成复线等情况,这必然导致大量的新建隧道与既有隧道近接或交叉,隧道的近接与交叉将会导致隧道施工难度的增加。本文依托浙江新岭隧道,围岩级别为V级,属于软弱围岩。根据工程提供的相关数据和资料,进行了调查、理论研究和相关计算,具体成果如下:(1)对新岭隧道右线洞口明洞段开挖进行了施工风险分析,经过综合分析,右线隧道洞口明挖段存在的主要施工风险为围护桩基坑施工,风险等级为高度(Ⅲ级),采空区与煤系地层施工,风险等级为中度(Ⅱ级),支护桩与仰坡施工风险等级均为中度(Ⅱ级)。(2)对新岭隧道暗埋段施工进行了风险分析,根据新岭隧道洞口段地质条件及施工工法,对主要的风险因素塌方、渗漏水、瓦斯风险、衬砌大变形等进行了详细的分析。对洞口的施工风险进行了评价,确定新岭隧道洞口施工风险等级并提出了减小本工程洞口施工的风险的措施与建议。(3)根据依托工程实际地质情况,利用大型有限元软件ANSYS进行数值模拟分析,新建隧道采用台阶法进行施工,分析了台阶法施工的隧道对既有隧道的三维建模数值分析,通过计算数据分析可以得出围岩、初期支护的局部位置(拱脚处)有应力集中现象,围岩、初期支护受力均低于强度规范值,都满足设计规范的强度要求;围岩、初期支护的位移变化均符合规范要求。最后对爆破进行了分析,得出新建隧道爆破施工时爆破振动振速在安全范围内,隧道爆破施工对既有隧道行车影响较小。
[Abstract]:In recent years, with the development of transportation industry, the country pays more and more attention to the construction of infrastructure. Since the 20th century, the amount of automobile transportation has been increasing, and the standard of highway route has been improved accordingly. Road tunnels are also gradually increasing. Under this background, because the tunnel is affected by many factors, a large number of tunnels are built, but sometimes the tunnel construction is limited by geology, topography and space, so many new tunnels are built near the completed tunnels, that is, the double lines of the existing tunnels are built. The new railway tunnel is parallel with the existing railway tunnel, and the double track is built at one time, which will inevitably lead to a large number of new tunnels and existing tunnels close to or cross, the tunnel close and cross will lead to the construction of the tunnel more difficult. This article relies on the Zhejiang Xinling tunnel, the surrounding rock grade is V, belongs to the weak surrounding rock. According to the relevant data and data provided by the project, the investigation, theoretical research and relevant calculation are carried out. The concrete results are as follows: 1) the construction risk analysis is carried out for the excavation of the Mingdong section at the right end of the Xinling Tunnel. The main construction risk in the open excavation section of the right tunnel is the construction of the retaining pile foundation pit, and the risk grade is the height (grade 鈪，

本文编号：2005515