基于数据融合的山岭隧道围岩稳定性评价方法

随着隧道信息化设计和施工的发展,如何利用隧道施工过程中的现场监测值对隧道安全进行准确合理的评价成为一项亟待解决的技术问题。本文针对新奥法隧道施工过程,提出了一种基于监测数据的施工安全评价方法,该方法通过将不同的监测数据相融合(如拱顶下沉和水平收敛),并结合数值计算方法,对隧道围岩的稳定性进行综合性评价。本文用折减节点力来模拟隧道初期支护前后的围岩应力释放过程,并计算出围岩稳定极限状态下的隧道变形值,作为围岩稳定性评价的重要依据。最后,将该方法应用到营盘山隧道的围岩稳定性评价中,根据隧道各断面水平收敛与拱顶下沉数据,计算隧道围岩稳定性安全系数,为施工决策提供理论参考。

Data Fusion Based Surrounding Rock Stability Assessment on a Deep Burden Tunnel

With the rapid development of tunnel informational design and construction, how to effectively use the in-situ monitoring data in the tunneling process to make an accurate and reasonable stability assessment is a significant technical problem. This article proposed a safety assessment method of a NATM tunnel based on the monitoring information. The new surrounding rock stability assessment is conducted by combining different monitoring data (i.e. tunnel crown settlement and horizontal convergence) with the numerical simulations. The stress release before and after the construction of the primary support is simulated by the reduction of nodal forces. The deformation under the ultimate stress release value is quantified and is taken as the basis for the stability assessment. Finally, the proposed method is applied to the stability assessment of the Yingpanshan tunnel. The factor of safety is calculated based on the tunnel crown settlement and horizontal convergence. The result of the stability assessment can provide reference to the decision making of the tunnel construction.