Segmental Model Test on Ultimate Bearing Capacity of a Cable Tower Anchorage Zone in a Cable-Stayed Bridge

Abstract

To determine the ultimate bearing capacity of the anchorage zone in a long-span cable-stayed bridge, a typical segment of the anchorage zone was selected for horizontal force mechanism analysis and model loading test, and its load-carrying behavior and deformation characteristics were subsequently analyzed. Results show that under the action of horizontal cable force, the bending moment is relatively large at the outer face of the end tower wall and inner face of the side tower wall, and the chamfer between the side and end walls becomes a critical section because of the combined action of tension, shear and bending. The failure mode is primarily concrete cracking: cracks appear in the end tower wall at 0.15P and penetrate the full height of the segment at 0.25P, while full-depth vertical cracks appear in the side tower wall at 0.20P. The horizontal load of the segmental mode increases nonlinearly with the deformation of the tower wall, and the ultimate bearing capacity reaches 329.70 kN, approximately 0.48P, indicating that the concrete tower wall alone cannot sustain the enormous horizontal cable force. Compared with the side tower wall, the concrete of the end tower wall is more sensitive to the horizontal cable force load. As the horizontal load increases, the load carried by the concrete is gradually transferred to the reinforcement because of the tensile cracking of the tower wall.

Keywords

composite bridge / cable tower anchorage zone / ultimate bearing capacity / concrete tower wall / model test

Conflict of Interest Statement

The authors declare that there is no conflict of interest regarding the publication of this paper.

Data Availability Statement

The data that support the findings of this study are available from the corresponding author upon reasonable request.

Funding

The research described in this paper was financially supported by Grants from the Natural Science Foundation of China (51808235), the Fujian Provincial Natural Science Foundation of China (2018J05083), the Promotion Program for Young and Middle-aged Teacher in Science and Technology Research of Huaqiao University (ZQN-813), the Huaqiao University Scientific Research Funding (16BS804).

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