Analytic method for calculating anti-slip safety factor between main cable and saddle in multi-tower suspension bridge

作者：Chai Sheng Bo; Xiao Ru Cheng; Wang Xiu Lan; Ren Xiang

来源：China Journal of Highway and Transport, 2016, 29(4): 59-66.

• Analytic method
• Anti-slip
• Anti-slip stabilities
• Bridge engineering
• Longitudinal direction
• Main cable
• Preliminary design
• Sag-to-span ratio

In order to guide the preliminary design of multi-tower suspension bridge in selecting parameter values, an analytic method for calculating safety factor of main cable slip on saddle was proposed. The main cables were equivalent to a series of springs in longitudinal direction. Analytic formula was deduced for calculating ratio of cable tension on both sides of the tower through investigating the internal force change of the main cable brought by live load under the most unfavorable load case, so the anti-slip safety factor of main cable can be obtained. The FE models of suspension bridges with four towers and five towers were established to verify the proposed formula. Some charts used for determining upper limit of stiffness of the bridge tower were given through sag-to-span ratio and ratio of live load to dead load. The influences of tower rigidity, sag-to-span ratio as well as ratio of live load to dead load on cable sliding stability were analyzed. The results show that the proposed method has a satisfied accuracy in calculating anti-slip safety factor of main cable on saddle, the ratio of live load to dead load and ratio of tower rigidity to cable stiffness have great influence on anti-slip stability of the main cable, and the effect of sag-to-span ratio on cable sliding depends on the tower rigidity.

• 出版日期2016
• 单位同济大学