Research On The Fatigue Property And Life Evolution Of A New Orthotropic Steel Bridge Deck

The orthotropic steel bridge decks are widely used in the long span bridges for theadvantage of light weight, large carrying capacity, and post-mold operations and so on,however, because of the numerous welded joints, the stress concentration on the joints andthe roofs support the traffic load directly, these will all cause lots of fatigue cracks on it inthe using, and these are also need to be solved quickly. In the text, aiming at the fatigueproblems of orthotropic steel bridge deck, the collusions can be drew as flowing:Firstly, in this text, the development and fatigue problems of orthotropic deck and theresearch level in domestic and abroad is introduced. The basic concept and theory oforthotropic deck are also elaborated, through the comparison on the classifications of fatiguedetails in domestic and external fatigue norms, advice will be put forward that Chinese fatiguenorms not only should draw lessons from foreign norms, but also should learns from fatiguenorms of railway bridges.Through the analyze and comparison on the standard fatigue cars models in differentcountries’ fatigue norms, the differences of live load between the road bridge and railwaybridge are pointed out, besides the differences of standard fatigue cars between thedomestic and foreign fatigue norms. And then through calculating and analyzing theconclusion that the collected standard fatigue car is reasonable.Finally, based on the two computing methods of constant amplitude fatigue damageand variable amplitude fatigue damage, a new orthotropic steel bridge deck put forward byacademicians Deng is analyzed and computed by means of finite element software Ansys.The new orthotropic steel bridge deck’s high fatigue property is checked under differentaxis load effect; furthermore a conclusion is drew that the key factor which affects thefatigue property of orthotropic deck is the vehicle’s axie load, and at the same time, theproperty of orthotropic deck under the overload vehicle is also checker, a point is put forwardthat it is necessary to improve and optimize the traditional orthotropic deck.