北京地区浅埋暗挖法下穿施工既有隧道变形特点及预测

发布时间：2018-09-18 11:21

【摘要】：城市地下工程建设中,新建隧道近距离下穿施工对既有隧道造成的扰动不可避免。正确分析及可靠预计既有隧道变形成为目前地下工程建设的热点问题。在预测隧道开挖引起的地表位移的经验法中,Peck公式最简便,应用也最为广泛。搜集北京地区10个近接下穿工程23组数据,对既有隧道实测变形进行拟合,发现绝大多数符合Peck公式分布规律。拟合得到地层损失率为0.116%~1.183%,沉降槽宽度系数为0.93~6.76。讨论新建隧道施工工法、辅助施工方法、新建隧道与既有隧道的埋深、既有隧道刚度、新建隧道双洞间距、变形缝位置等因素对经验参数的影响,给出经验参数的修正公式。将经验参数修正公式与Peck公式相结合,为北京地区受新建隧道下穿施工影响的既有隧道变形提供一个简便、快捷的预测方法,并通过工程实例验证了预测方法的有效性。研究成果可对未来北京同类工程和其他地区近接工程设计和施工提供参考,同时对丰富同类工程数据库具有重要意义。
[Abstract]:In the construction of urban underground engineering, the disturbance of the existing tunnel caused by the construction of the new tunnel at short distance is inevitable. Correct analysis and reliable prediction of existing tunnel deformation has become a hot issue in underground engineering construction. In the empirical method of predicting the surface displacement caused by tunnel excavation, the Peck formula is the most simple and widely used. This paper collects 23 groups of data from 10 near-connection underpass projects in Beijing area and matches the measured deformation of existing tunnels. It is found that most of them are in accordance with the distribution law of Peck formula. The loss rate of formation is 0.116 and the coefficient of width of settlement trough is 0.93 and 6.76 respectively. This paper discusses the influence of the construction method, auxiliary construction method, the buried depth of the new tunnel and the existing tunnel, the stiffness of the existing tunnel, the distance between the two holes of the new tunnel and the position of the deformation joint on the empirical parameters, and gives the correction formula of the empirical parameters. The empirical parameter correction formula is combined with the Peck formula to provide a simple and fast prediction method for the deformation of the existing tunnel affected by the underpass construction of the new tunnel in Beijing area, and the effectiveness of the prediction method is verified by an engineering example. The research results can be used as a reference for the design and construction of similar projects in Beijing and other areas, and it is of great significance to enrich the database of similar projects.
【作者单位】：北京交通大学城市地下工程教育部重点实验室;北京城建设计发展集团股份有限公司;
【基金】：国家重点基础研究发展计划(973)项目(2010CB732102) 中央高校基本科研业务费专项资金资助项目(2012YJS076) 北京市科委计划项目(Z121100000312021)
【分类号】：U455.4

【参考文献】