Research On Structural Robustness For Cable Loss In Cable-stayed Bridge Without Back-stays

The robustness of the bridge structure has become a hot research topic in engineeringfield with the bridge safety accidents occur frequently. Analysis of bridge accident damagemechanics characteristic of the residual effect after the structure is important to ensure thesafe operation of the bridges. However, engineering rarely on the cable-stayed bridge withoutback-stays to carry out robust research. This paper will carry out cable fault systemrobustness research with cable-stayed bridge without back-stays as the background.The mainresearch contents are as follows.1、Analysis the structure characteristics of the cable-stayed bridge without back-stays,and to study the robust standard. Developed for structure failure criteria in this paper.Describes the redundancy analysis method of the structural system of cable-stayed bridgewithout back-stays and sensitivity analysis indicators of structure of the whole bridge cable.To introduce Structure static analysis and put forward the dynamic analysis method suitablefor in this paper.2、Analysis of cable-stayed bridge without back-stays for redundancy and determine thesensitivity of the different structure of the whole bridge cable, to determine the key region ofcable, and laid the foundation for subsequent damage analysis.3、Analyzes the cable damage residual structural static and dynamic performancecharacteristics of cable-stayed bridge without back-stays, got the stress of residual cableunder different cable damage and main girder and main tower linear, stress characteristics andchange rules. Got the static and dynamic characteristics of cable-stayed bridge withoutback-stays structure through the comparison and analysis, which determine the safetythreshold value of the structure under different analysis method.Through research, this paper concludes that structural system robustness characteristics:The of the bridge structure is strong when unilateral stay cables fracture, the bridge structurewill not be destructive when the unilateral stay cable fracture collapsed. Girder due to thelarge deflection of inappropriate operations when more than four stay cable rupture on thesame side. Girder due to the large deflection of inappropriate operations when more than fourstay cable rupture on the opposite side. Judging from the strength criterion, the bridge robustness control threshold for no more than10root (5pairs), the structure security underthe condition of no more than10consecutive stay cable rupture on the opposite side.