The Local Stress Calculation And Analysis For The Critical Parts Of Fuhe Bridge

The Fuhe Bridge is an extraversion-asymmetric-curve arch bridge with a main-span of150meters,and the whole width of its deckis up to69meters.Due to itscomplex spatial-shaped structure system and the great width-to-span ratio of the deck,the global and local stress distribution of the bridge become very complicated.And the local stress concentration often occurs because of the unreasonable conformation, which can even endanger the security of the whole bridge.Therefore,local analysis and optimized designfor the critical parts of a bridgeisquite necessary to be proceeded.Taking Fuhe Bridge as a project background, the local stress distribution of its critical parts including the orthotropic steel deck, the anchorage zone of the elastic cable and the stiffening ribs of the support is analyzed by using finite element method in this dissertation. Some reliable reference datas are provided for the bridge design and optimization.In the beginning, the development process andcalculation method of steel bridgewere introduced briefly, and the theory of finite element method was expounded in detail.Then, the local stress distribution for orthotropic steel girders under several load cases was analyzed by using ANSYS software. The mechanical characteristics of each plate of girders were discussed, and some reference opinions for bridge design are presented. Later, the finite element model of steel anchor box wasestablished to analyze the stress distributionwhile the anchor boxbearing the max cable force, and the stiffening plates of the anchor box was optimized.To avoid the stress concentration, the combination method of contact stress analysis technology and preloaded units were also used to analyze the anchorage structure.Finally,the finite element models of the stiffening ribs at vertical and horizontal bearings were established respectively to analyze the stress distribution. Thus rationality of the ribs’design is verified in theory.The support forces of the superstructures can be transferred to substructures smoothly by the ribs.In conclusion, the theoretical calculation results provide a designbasis for the local structure of the Fuhe bridge, which may also be used in other similar bridges.