摘要
为明确隧道开挖时易于引发安全事故的关键位置并预测地层变形趋势,以保证隧道施工和周围构(建)筑物的安全,采用Ansys通用有限元软件对北京地铁7号线广双区间隧道开挖过程进行了数值模拟分析,并结合实际监测结果对隧道开挖过程中地层变形和应力重分布的变化规律和安全关键位置进行了总结;通过对随机介质理论方法的优化研究,推导出简单可行的优化计算公式。结果表明,隧道开挖中拱顶、拱腰和拱脚位置为变形较大和应力分布集中的关键安全位置,优化后的随机介质法计算公式用于地表沉降的安全预测分析是可靠的。
The paper is to present our analysis of the ground surface settlement due to the tunnel construction with the optimized study in hoping to predict and forecast the safety of the tunnel construction, as well as the buildings and structures nearby. In this paper we have done a numerical simulation analysis by using Ansys general finite element software in the study of the tunnel excavation process of Guang-Shuang section of Line 7 of Beijing subway construction network. Comparing the monitoring data with the simulation results, we have made clear that the measured data are consistent with the numerical simulation results. It can conclude that the basic change regularity of the stress redistribution and the ground deformation situation. The above research facts help us to make sure the key positions that are prone to accidents in the different stages of the subway excavation. In so doing, the simulation results of ours may help to provide a guide to the design of the subway tunnel excavation and facilitate the enormous calculation tasks. Based on the optimization of the random medium theory research, we have arrived at the simplistic and feasible optimal formula. The optimized calculation results and the available monitoring data prove to be in accordance with the monitoring results. In addition, there are two key parameters must be determined when we use the optimized formula： the tunnel diameter convergence value of the tunnel diameter and the main influential angle β. And, finally, we have arrived at the other necessary conclusions, such as the vault hance and the arch foot of the tunnel, which are the key positions to ensure the safe excavation. Making clear where there are points to be strengthened, we have decided to put more and better reinforced concrete to the key positions. Thus the optimized formula of the random medium theory can help to prove the ground surface subsidence prediction and make the design and construction jobs more safe, secure and reliable.
出处
《安全与环境学报》
CAS
CSCD
北大核心
2014年第2期26-31,共6页
Journal of Safety and Environment
基金
住房与城乡建设部科学技术项目(2012-R1-16)
陕西省教育厅专项科研计划项目(2010JK638)
关键词
道路工程
安全预测
地表沉降
数值模拟
随机介质理论
road engineering
safety predictions
ground surfacesettlement
numerical simulation
random mediumtheory
