Abstract: Currently, there is a lack of information on the theory and practice of the relatively new tunnel-type anchorage for suspension bridges. Firstly, the safety control indexes commonly used in tunnel anchorage engineering are summarized from two aspects of anti-draw bearing safety and anchorage deformation control. Then the research methods are analyzed for the bearing capacity and deformation characteristics of tunnel-type anchorage, respectively. Finally, the achievements of more than 10 tunnel anchor projects in the project team for the past 20 years are summarized. It is concluded that the deformation of the existing and under construction tunnel-type anchorages are generally in the order of millimeters, and the overload stability coefficient of the anchorage is usually greater than seven under tens of thousands of tons load of the main cable. It shows that the existing and under construction tunnel-type anchorages have a sufficient safety margin, and the design of tunnel-type anchorage can be optimized to a certain extent. At the same time, it is pointed out that the current proposed deformation control standard of tunnel anchor is based on the bridge structure and does not take into account the restrictions on the deformation of materials such as anchor body itself and surrounding rock. The bearing capacity of tunnel anchorage summarized in this paper is mainly from the bearing capacity of anchor concrete and surrounding rock system, without considering from other factors such as the strength of steel strand material. The conclusions in this paper have their specific conditions and scope of application, and further research on the bearing mechanism of tunnel anchor system is required.

Key words: suspension bridge, tunnel-type anchorage, bearing capacity, deformation characteristics