Research on the Fatigue Performance of the Welded Joint of the Orthotropic Deck on Wuhan Tianxingzhou Bridge

Wuhan Tianxingzhou Bridge is the major bridge of combined highway and railway Yangtze Bridge.Orthotropic plate structure is adopted for its highway bridge deck.Finite element software ANSYS and welding fatigue test method are adopted to study the fatigue performance of the key welded joints(trough splice welding and trough crossbeam welding) on the orthotropic deck.An integral model of two spans is built with ANSYS,and the deck stress is analyzed according Technical Standard of Highway Engineering.The most unfavorable load position is determined and then the maximum stress ranges of the key welding positions are obtained,of which the trough splice welding is 28.6 MPa and the trough crossbeam welding is 39.66 MPa.The result of fatigue test shows that the welding toe is the vulnerable spot of the welding joint.The maximum allowable stress range of trough splice welding and trough crossbeam welding obtained from the fatigue test is 89.31 MPa and 49.14 MPa respectively,which are higher than those obtained from the finite element calculation.It shows that the fatigue performance of the key welded joints of the orthotropic deck can meet the requirement.