[This article belongs to Volume - 51, Issue - 03]
Gongcheng Kexue Yu Jishu/Advanced Engineering Science
Journal ID : AES-16-10-2021-26

Title : Creep Test of Tunnel Anchor Providing Reaction Force of Xingkang Bridge
WEN Lina, CHENG Qiangong, CHENG Qiang, GUO Xifeng,

Abstract :

There are few in-situ creep test data of tunnel anchor for suspension bridge. To obtain the creep deformation law of tunnel anchor of Xingkang Bridge on Yakang Expressway and enrich creep test data of tunnel anchor of super-large suspension bridge, creep tests of 1∶10 in-situ shrinkage model of the Ya’an side slope tunnel anchor of Xingkang Bridge were carried out, based on the specific geological conditions in the Ya’an side slope tunnel anchorage area of Xingkang Bridge and the similar theory of elastic mechanics. According to the creep characteristics of the model anchor and surrounding rock mass under 1.0P, 3.5P and 7.0P loads, the whole creep process of the model anchor, surrounding rock and interfacial dislocation were analyzed. The results show that under 1.0P, 3.5P and 7.0P loads, the maximum creep deformation of anchor body was 0.62 mm, 0.97 mm and 1.58 mm, the maximum creep deformation of surrounding rock was 0.49 mm, 0.85 mm and 1.38 mm, and the maximum creep deformation of anchor body and surrounding rock was 0.15 mm, 0.64 mm and 1.43 mm, respectively. On the basis of in-situ scale tests, the three-dimensional viscoelastic-plastic numerical analysis of the interaction between anchorage and surrounding rock mass was carried out by using FLAC3D finite element software. The comparison between the field measured values and numerical analysis results shows that the measured creep deformation and calculation results of the anchorage and surrounding rock of the Ya’an side bank slope tunnel of Xingkang Bridge have the similar evolution trends and range of amounts. The creep of tunnel anchorage and surrounding rock mass of Xingkang Bridge on Yakang Expressway belong to stable creep stage under various loads. The long-term stability of suspension bridge was not affected by the creep of anchorage and surrounding rock mass. The test results provide a basis for the reliability evaluation of the tunnel anchorage system of Xingkang Bridge, and also provide a reference for similar engineering designs.