Mechanical Analysis Of Steel Bridges Deck Pavement Under Vehicle Loadings

With the appearance of the long span bridges,scholars and researchers for the studies on pavement system of the steel bridges are also deepening.In the engineering examples,there is a synergy between pavement and steel bridge deck.The external load is shared by the pavement and the steel bridge deck.There is always a cohesive layer between pavement and steel bridge deck.And the material properties of the bonding layer are very far from the paving layer and the steel bridge deck.This makes the bonding layer become the weak layer of the steel bridge deck pavement system.In this paper,to use the ANSYS finite element software to establish the model of typical orthotropic steel deck pavement system with bonding layer and to simulate the different contact states between layers.This mainly studies the mechanical responses of continuous model and contact model under vehicle load.To analysis the variation rules of the steel bridge deck pavement system’s stress and strain under the influences of pavement’s modulus,bonding layer’s properties,bonding states and delamination.The main research contents are as follows:Firstly,the stress of the pavement system for orthotropic steel bridge decks with/without mediastinal plate under the vehicular loading are studied.And the effects of the bonding layer’s thickness,the bonding layer’s elastic modulus,the pavement’s elastic modulus,and bonding layer as anisotropic unit on the pavement system’s mechanics properties are discussed.The results show basically consistent rules in analyzing the mechanics properties of the pavement system with mediastinal plate and without mediastinal plate under the influence of these factors.We should consider the influences of these factors and the mechanical properties of materials when designing the pavement system.Secondly,the effects of the contact states between the bonding layer and the steel bridge deck on the mechanics of steel-deck pavement are analyzed.The contact states between the bonding layer and the steel bridge deck are completely continuous,semi continuous and completely smooth.The analysis results show that improving the bonding state between the bonding layer and the steel bridge deck is benefit to the pavement system’s mechanics properties.In the design of the pavement system,using the contact states between the bonding layer and the steel bridge deck are completely continuous as the criterion.Then the design can meet all the contact states.Finally,the bonding layer destruction of the steel bridge deck pavement structure through defining element life and death element in contact model is simulated.The effects of the different locations of delamination,the areas of delamination and the different forms of delamination on the stress of orthotropic steel deck pavement system are analyzed.The characteristics of the stress distribution and the extension of delamination of the steel bridge are demonstrated by means of the map of contact stress between layers.The results show that the pavement deck’s stress and the stress of bonding layer are the maximum when the load is over the area of delamination.If the position of delamination is far from the position of the load,the effects on pavement deck system are small.This shows that the effect range of load is limited.And it is reasonable to adopt the simplified calculation model.The delamination damage is extremely disadvantageous to the pavement system,and it should be repaired in time to prevent delamination from extension.