Abstract:

This paper introduces the theory and process of the configuration calculation of main cable for self-anchored suspension bridge based on the methods of segmental catenary and parabola, put forwards a nonlinear programming method for the iterative calculation by considering the flexural effect on the axial rigidity of the beam, and verifies the accordance of the proposed method with the traditional influence matrix method. It is demonstrated by the calculated results of self-anchored suspension bridge with typical span that, by using the parabola method, the calculation error of cable configuration of a completed bridge under constant loads is small enough for the general engineering design and construction, but the errors arising from the calculation of free cable coordinate and saddle pre-displacement are both significant. An error analysis of the configuration of the main cable for a self-anchored suspension bridge is finally performed by means of parabola method with respect to the rise-to-span ratio, the main span, the side span-to-middle span ratio and the stress safety coefficient of main cable.

Key words: self-anchored suspension bridge, segmental catenary, axial rigidity, influence matrix, nonlinear programming, main cable, configuration, saddle pre-displacement