The Study On The Failure Mechanism And Relevant Countermeasures Of The Suspended Bridge Deck System In The Half-through CFST Arch Bridge

The CFST arch bridge has developed quickly in China. Meanwhile, there are manydisease problems in the operation period owing to the structural design andcomputational theory is not well developed. Especially for some of the half-throughCFST arch bridges, the vibration caused by the vehicle is very serious and and thebridge dynamic performance is rather poor because of the bad integrity of the decksystem. The failure problem of the bridge deck system is particularly prominent. Thepaper analyzes the failure mechanism of the type of suspended bridge deck system andresearchs its relevant countermeasures.This paper studies the structure of the suspended bridge deck system and themechanical characteristics in depth to get the reason of weak links between thecrossgirders and poor integrity of the deck system. It determines bridge deck systemperformance factors by analyzing the force situation of the constituent members. Basedon the theoretical analysis and finite element model analysis, this paper researchs theexisting simplified calculation methods of suspended bridge deck system and evaluatestheir applicability.This paper studies the vehicle-bridge coupling vibration. Then by using an improvedseparation iterative method, the vehicle-bridge coupled vibration program is establishedby using MATLAB and ANSYS softwares. The program is used to study thevehicle-bridge coupling vibration performance of Changqing Bridge in Shenyangthrough the deck evenness, vehicle speed and bridge structural damping.The local entity model and the space grillage model of overall bridge decksystem is used to thoroughly analyze the static and dynamic performance of thesuspended bridge deck system through width of crossgirders, height of crossgirders,thickness of the deck and cross-section area of suspenders. According to the wholeanalysis before, the paper synthetically elaborates the failure mechanism of thesuspended bridge deck system.Based on the failure mechanism of the suspended bridge deck system, it proposessome suggestions to the bridges’ design. Some reinforcement and retrofit methods arebeen proposed to deal with the destruction problem of old bridge deck system. And the application and rationality of the methods are been evaluated. It analyzes the effects onthe bridge static and dynamic performance by using the method of adding longitudinalbeams and proves it to be an effective method. Also the paper proposes that applying anew type of damping device on this type of deck system. It proves that the device canimprove the components’ condition and reduce the vibration of the deck system. And itsgood effectiveness is verified in the end.