Experimental Research on Stability of Cable-Stayed Bridge with Central Cable Plane During Large Cantilever Swivel Process

This paper discusses the stability of the cable-stayed bridge under different loading conditions during the large cantilever swivel construction process. A railway crossing of the second phase of West Extension Project of Jinnan Avenue in Dazhou is used for a case study. In accordance with the similarity ratio theory and stiffness similarity principle, a segmental model of 1 : 10 scale was prepared to test the stresses in the stands, upper turntable and superstructure as well as stay cable forces, and distribution of girder-end deflection and rotation angle, under four loading conditions, specifically when an angular velocity is set at 1.2, 1.8, 2.4, 3.0, and 3.5 (°)/min, respectively, accelerations calculated at a rotation time of 40, 20 and 10 s, respectively, lateral eccentric loading with a self-weight bias of 0, 1%, and 2%, respectively, as well as wind loads under calm winds and winds of scales 6 and 8. The results demonstrate that angular velocity exerts an effect on the stresses in the stands and upper turntable to a degree, but significant effect on the stresses in the superstructure, stay cable forces, girder-end deflection and rotation angle. Angular acceleration has minor influence on the rotation stability of the cable-stayed bridge. The lateral eccentric loads and wind loads arc highly correlated with the rotation stability of the cable-stayed bridge. It is recommended to keep the angular velocity less than 3. 0 (°)/min, lateral eccentric loads less than 2% of total loads, and wind loads imposed by winds below scale 6. © 2023 Wuhan Bridge Research Institute. All rights reserved.