Prediction Analysis of Deformation Characteristics During Construction and Operation of Tunnel Anchor Structure System in Soft Rock

As one of the important components of suspension bridge, the main role of tunnel anchor is to transfer the bridge load to the anchor plug, through the anchor plug to the surrounding rock, so as to ensure the stability and safety of the suspension bridge. The deformation and stability of the tunnel anchor plays a vital role in the normal and safe operation of the suspension bridge, while the surrounding rock, as the carrier of the transmission force of the tunnel anchor, also affects the stability of the tunnel anchor, especially in the soft surrounding rock conditions should pay more attention to the deformation and stability of the tunnel anchor. In this paper, FLAC-3D is used to perform 1:1 3D elastic-plastic numerical simulation of the tunnel anchor and its surrounding soft rock structural system on the north side of the river at the Wujiagang Yangtze River Bridge in Yichang, China. The anchor plug and its surrounding rock system are simulated and analyzed in three aspects: construction period, bearing period, and long-term operation. The displacement and deformation patterns of the anchor plug and the surrounding rock structure under different conditions are studied. The conclusions verify that the deformation and stability of the solid tunnel anchor under this soft rock condition can meet the engineering safety requirements.