The Research On Key Techniques For Suspender Tension Control Of Long-span Three-tower Self-anchored Space Cable Suspension Bridge

In recent years,my country’s economy has developed rapidly.At present,various beautiful and peculiar bridges have appeared in the country.Self-anchored suspension bridges,as a kind of beautiful linear bridge type,are less dependent on construction conditions and are frequently used in various bridges.Appears in small and medium span bridges.In the industry,there have been relatively complete and mature researches on the design and construction of ordinary single-tower and double-tower self-anchored spatial cable suspension bridges,and many instructive results have been obtained.However,since there are few actual engineering cases of large-span three-tower self-anchored spatial cable suspension bridge,the sling tension control technology for this type of bridge is not systematic enough.This article relies on the domestic Jinan Phoenix Road three-tower four-span self-anchored spatial cable suspension bridge In the construction in progress,the system has systematically studied the tension control problems of this type of bridge sling,which provides a reference for the subsequent analysis and research of the sling tension of the same type of bridge structure.By reading relevant literature,review the current research status at home and abroad,as well as the force characteristics,structural calculation theory,and sling tension characteristics of the three-tower self-anchored space cable suspension bridge,and compare the traditional self-anchored suspension bridge,the traditional three-tower suspension bridge,and the traditional space The control index of the cable suspension bridge proposes a new type of suspension control principle for the large-span three-tower self-anchored space cable suspension bridge.Because this bridge has the largest main span of the same kind of bridge in the world,under the premise of defining the control index of sling tension,taking the designed state of the bridge as the target state,according to the calculation and analysis theory of suspension bridge,two different sequence of cable tension schemes are proposed,and the finite element model is established by using the general software bnlas;through the main cable saddle pushing times and amount,tower deflection and stress Based on the analysis of the control parameters,such as the allowable maximum tension force and extension times of suspender,the installation time of bridge tower support,the stress and displacement of stiffening beam,a new sling tension scheme for long-span three tower self anchored space cable suspension bridge is proposed.Through the analysis of the whole process of space cable conversion,taking the horizontal and longitudinal installation angle of the sling as the control index,and using the number of temporary sling arrangement as the construction economic index,different tensioning schemes are compared.It is concluded that the tension scheme from the bridge tower to the middle of the span is more competitive in the long-span three tower self anchored space cable suspension bridge.Based on the analysis of asymmetric tension of sling,the action law of asymmetric tension on tower deflection and tower bottom stress of long-span three tower self anchored space cable suspension bridge is obtained,and suggestions for site construction are given.