Steel-concrete composite modularized bridge pylon: bearing capacity of the cable-anchorage

Abstract

Steel-concrete composite bridge pylons adopted factory prefabrication and modularized construction technology, realizing the advantages of high stiffness, cost-effectiveness, and improved construction efficiency, and is increasingly adopted in the construction of cable-stayed bridges. However, large-scale model tests on the structural behaviour of steel-concrete composite bridge pylon anchorages are still insufficient. Therefore, this paper focuses on the structural behaviour of cable-pylon anchorage zone subjected to the horizontal component of the cable force by utilizing six segmental models, including with or without the participation of inner steel plates, the direction of anchor tube deployment being inclined or horizontal, different anchor plate sizes, and a reinforced concrete segmental specimen. The test results unequivocally underscore the exceptional ultimate bearing capacity and ductility of the steel-concrete composite cable-pylon structures. Notably, the test results emphasize the impermissible anchor plates with inadequate dimensions, which leads to fragile damage and a substantial reduction in the bearing capacity of the anchorage zone. Furthermore, the load distribution ratios analysis revealed the average load distribution among the sections of steel plates and infilled concrete of the anchorage zone. Finally, an efficient analysis method for predicting the ultimate load-carrying capacity of steel-concrete composite cable-pylon anchorage is proposed based on the test results. The comparison between the equations and test results demonstrates that the analysis method is accurate enough to serve engineering communities. This work contributes to construction process recommendations and design calculations for prefabricated and modularized construction of bridge cable pylons.