AN INCREMENTAL DESIGN ALGORITHM OF ARCH AXIS OF ARCH-SHAPED TOWER FOR CABLE-STAYED BRIDGE

The design of arch axis is a difficult task for cable-stayed bridge with arch-shaped tower. Assuming a polyline for the arch axis, an incremental algorithm is presented for the geometrical analysis of arch-shaped tower. The nodal coordinates of the arch are computed incrementally according to the targeted distribution of bending moments and central thrust force. Only vertical components of cable forces are required by this algorithm, and the total cable forces can be determined during the shape analysis of arch axis. Optimization technique is employed for the determination of vertical components of cable forces. The validty and effectiveness of the proposed arlorithm are illustrated with a case study of a cable-stayed bridge with arch-shaped tower.