Optimization of Cable Pre-Tension Forces in Multi-Tower Cable-Stayed Bridges with Crossing Cables Considering the Dead Load Allocation

In a multi-tower cable-stayed bridge with crossing cables, the crossing cable pre-tension forces can not only control the vertical displacement of the deck under dead load, but also affect the structural performance. This paper presents an optimization method for pre-tension forces of crossing cable multi tower cable-stayed bridge. This method uses the conic quasi-uniform B-spline curve to represent the distribution of cable pre-tension forces, and the shape of the curve is optimized by particle swarm optimization algorithm. The displacement of the tower and deck under dead load and the displacement of the deck under dead load + live load are taken as optimization objectives, and the two-objective optimization problem is solved by linear weighting method. Finally, the effectiveness of the proposed method is verified by comparing it with practical methods. The calculation results indicate that when the stress level of the cable under dead load is consistent, this method minimizes the vertical displacement of the deck under dead load and live load.