Experimental Study On High Performance Pavement Of Steel Box Beam Deck

Steel box girder bridge deck pavement is one of the key technologies in the construction of steel box girder bridge.At present,it is also a worldwide problem that restricts the development of steel box girder bridge.This paper takes the composite pavement structure based on the rigid bottom layer of lightweight concrete as the research object,and intends to treat steel from two aspects: paving material and paving structure,in order to obtain the pavement structure which can effectively improve the stress condition of steel deck pavement and improve the pavement performance of steel deck pavement.Firstly,in view of the pavement materials,this paper used the hybrid fiber to improve the performance of asphalt mixture,the influence of polyester fiber,basalt fiber and wood fiber on the performance of asphalt mixture was studied by orthogonal design test,and the optimum ratio of the three fibers was determined.the experimental results showed that under the optimum blending ratio,high temperature stability of the hybrid fiber asphalt concrete performance has been effectively promoted,more suitable for steel bridge deck pavement layer.In order to prepare lightweight concrete to meet the requirements of steel bridge pavement,this paper optimizes the mix ratio of lightweight concrete according to the specification and previous research experience,and studies it by orthogonal design test.The influence of water-cement ratio,fly ash content and steel fiber content on the mechanical properties of concrete is investigated,and the optimum mix ratio of light concrete is determined.the test results show that: in this paper,preparation of lightweight concrete with good work-ability,mechanical properties and fully meet the requirements of steel bridge deck pavement.Secondly,the finite element analysis model is established for the pavement structure.Through the finite element analysis of the pavement structure,the stress variation law of the composite pavement structure under different position loads is studied,and the main control stress and the most unfavorable load position of the upper and lower layers are determined,which provides the theoretical data support for the pavement scheme.At the same time,the law of stress variation of pavement under different pavement parameters is studied,and the reasonable suggestions are put forward for the main parameters of composite pavement structure.Finally,through the indoor test and theoretical calculation,the inter-layer shear resistance of the composite pavement scheme is studied,and the tests results are compared with theoretical analysis.The results show that the inter-layer shear resistance of the pavement scheme fully meets the mechanical requirements,and further verify the feasibility of the pavement scheme.