Influences of Random Deviations in Cable Tension Force on the Stress State of a Composite Girder Cable Stayed Bridge Without Backstays

Considering the limitations in construction technology, deviations in the initial tension force of cables often exist. Herein, we established an analytical model through the finite-element analysis software ANSYS to study the influences of random deviations in cable tension force on the stress of pylon, beam, and cable, as well as the deformation of pylon and beam and the structural reliability of the construction of Dongguanshuidao bridge. This bridge is a composite-girder cable-stayed bridge without backstays. In our model, Monte Carlo method and Latin hypercube important sampling technique were used. Sensitivity factor and percentage of structural response were analyzed, and reliability analysis of the control-section stress was carried out. Results showed the following. First, the stress of pylon, beam, and cable, as well as the deformation of the pylon and beam, presented significant asymmetry. The related sensitivity factors had high disparities; among them, the standard deviation of stress and deformation in the side span of the beam and pylon were the least impacted by the initial cable force. Second, the initial cable force had the most influence on the final cable force of the cable, and the related number was consistent. The error level of the initial cable force was controlled according to the guidelines for the design of a highway cable-stayed bridge.