Study on Creep Test of In-situ Scaling Model of Suspension Bridge Tunnel Anchorage

In order to obtain the creep deformation law of tunnel anchor of Luding Dadu River super-large suspension bridge on Yakang Expressway, creep test of 1∶10 in-situ scale model of tunnel anchor was carried out according to similarity theory. The graded loading test of model anchor was carried out with gas-liquid loading system, the creep process of model anchor, surrounding rock and interface dislocation under 1.00P (single design tension of scale model), 3.50P, and 7.00P loads were analyzed. The three-dimensional viscoelastic-plastic simulation analysis of creep of anchorage and surrounding rock mass was carried out by FLAC^3D, and the simulation value was compared with the measured value. The results show that under 1.00P, 3.50P, and 7.00P loads, the maximum creep of anchor body are 0.62, 0.97 mm, and 1.58 mm, the maximum creep of surrounding rock are 0.49, 0.85, and 1.38 mm, and the maximum creep of anchor body and surrounding rock are 0.15, 0.64 mm, and 1.43 mm, respectively. The measured creep deformation of anchorage and surrounding rock is equivalent to the calculated value, and the creep trend is basically the same. The tunnel anchor and surrounding rock of Yakang super-large suspension bridge belong to stable creep under various loads, the creep of anchorage does not affect the long-term stability of suspension bridge under normal design loads.