Biaxial Fatigue Behavior Evaluation of Orthotropic Steel Deck
This study investigates the fatigue performance of the orthotropic steel deck under biaxial stresses.The 3D finite element model of an orthotropic steel deck involving the welded joints of the top plate,U ribs and diaphragms was developed based on the Shengli Huanghe River Bridge in Dongying,and the biaxial fatigue performance of the orthotropic steel deck was analyzed using the equivalent structural stress method.Model tests were conducted to verify the numerical simulation and predict the fatigue life of the welded joints.It is shown that cracks at the welding initiation points of the arc cut-outs start from the welding toes underneath the diaphragms,undergoing a conceiving,propagating and failure stages,and at the failure stage,the cracks are the Ⅰ-Ⅱ mix cracks,with the Ⅱ-cracks play a dominant role,which are also the primary fatigue failure modes of the orthotropic steel deck system.The welding toes of the top plate and the welding toes at welding initiation points of the arc cut-outs are in biaxial stress state,the in-plane shear stresses are significantly associated with fatigue stresses,when using the uniaxial fatigue stresses to predict fatigue life,there would be great errors,thus it is not proper to use uniaxial stress state in the fatigue life design.The fatigue life calculated by the combined equivalent structural stress method agrees well with the test result,and the crack initiation points determined using the maximum calculated values of each welded joint are also in agreement with the test results.The fatigue life predicted using biaxial fatigue stresses agrees well with the test result,with high prediction accuracy.
orthotropic steel deckequivalent structural stress methodbiaxial stressfatigue performancefinite element methodfatigue test
万方数据
维普
