Stabilitation Research of the Tunnel Anchorage of Dadu River Bridge in Luding in Yaan to Kangding Expressway

Abstract

Based on features of indoor rock mechanics test, the in situ test and rock mass classification result, through established numerical analysis model of the tunnel anchor model drawing test, using the model observed values of surrounding rock deformation, using intelligent inversion method to inverting the displacement creep and mechanical parameters and provides more accurate and reasonable rock mass mechanics parameters to analyze the stability of surrounding rock tunnel anchorage of Dadu River bridge from Yaan to Kangding expressway in Lu Ding. This paper uses LSSVM and PSO analysis model and FLAC3D numerical methods to realize the intelligent displacement inversion. Through the anchor parameters inversion of the model, and establish the solid bridge anchor numerical model, analysis of anchor tunnel excavation, load and overload condition of deformation and internal force, and then analyze the stability of tunnel anchor. Under the design load, anchorage roof and side wall stress relaxation zone in the plastic zone, floor rock mass basic in flexible working condition. Increase the force of main cable and 7P, shear failure and anchor rock contact area, increase the displacement of anchorage is nonlinear. Under the overload condition, the anchor rock rupture increased significantly and produce compression, the plastic zone to the development of deep surrounding rock anchorage above, failure mode for compressive shear failure. The conclusion to provide technical support for tunnel anchor design, at the same time, provide reference for similar projects.