| As an important part of bridge engineering,steel bridge deck pavement has always been a worldwide problem,which has caught the attention of industry and society.Under the special traffic and climate conditions in China,steel bridge pavement disease is frequent and the maintenance is lagging behind,which lead to the actual service life of steel bridge deck pavement are difficult to reach the design life.In a variety of failure forms of steel bridge deck pavement,fatigue cracking,shearing delamination and rutting deformation are the most typical diseases.And all the steel bridge deck pavement engineering can not be avoided,but also they are the most destructive form for the quality and integrity of all the steel bridge deck pavement engineering.In this paper,the three kinds of diseases are classified as structural damage.The focus of present research direction in steel bridge deck pavement technology is how to curb the occurrence of structural damage and improve the quality and durability.In this article,based on the experimental study about material performance and modulus paremeters of steel bridge deck pavement,the mechanical response and temperature field are analyzed,the prediction models of steel deck bridge pavement fatigue cracking and shear delamination based on damage mechanics and rutting deformation of paving structure are established.Meanwhile,relying on the Maanshan Yangtze River,a structural damage prediction method is improved,which can be used to guide the steel bridge deck asphalt pavement.The main research results are as follows:(1)Based on the test of performance of steel bridge deck pavement materials,the five loading composite beam test model,the field testdata of graded loading,and the result of finite element analysis,the deformation modulu of pavement material is obtained.At the same time,according to the structure size parameters of composite beam test model,the calculation method of deformation modulus is established which is based on analytic method,and the results are used to compared with numerical method.Based on the this method,the deformation modulus of GA10 and SMA10 under different temperature conditions are determined using analytical method by the composite beams loading deformation test under the condition of-5 ? ~ 55 ?,which provid a strong support for the subsequent steel bridge deck pavement mechanics analysis.(2)Based on the structural parameters of orthotropic steel bridge deck system,finite element analysis model is established by using Abaqus software,and the key influence parameters for three kinds of typical structure damage are determined,such as the most unfavorable loading of maximum flexural strain on the surface,maximum interlaminar shearing stress and the maximum vertical displacement.On this basis,according to the material parameters of different temperature conditions,the influence rules of loading level on maximum flexural strain,maximum interlaminar shearing stress and maximum vertical displacement are analyzed.(3)On the basis of the analysis of influencing factors of steel bridge deck pavement temperature field,the boundary conditions of it is determined.Then Abaqus software is adopted to establish the finite element model of the surfacing layer with steel box girder,and multiple temperature condition parameters of representative days are used to analysis the laws of the change of temperature field,such as the temperature field of the surface of steel bridge deck pavement,between the layers of SMA10 and GA10,and the steel plate.And then a calculation model was set up,which is about the temperature change with environmental conditions,this model is validated verification and revised by using field monitoring data,and formed the final calculation model which can be used to guide the analysis of steel bridge deck temperature field.(4)Using the method of four point bending fatigue test,the influence of temperature and load conditions on the fatigue life of elastomer modified asphalt SMA is determined by the bending fatigue test under the condition of three temperature and multiple strain levels.Through the data fitting analysis,the temperature function is introduced to establish the classical fatigue equation of elastomer asphalt SMA.Based on the analysis results of the maximum flexural strain of asphalt pavement under different temperature and loading conditions,the maximum times of different axle loads in different temperature range is calculated.According to fatigue damage theory,the sum of damage degree at different actual axle loads conditions are used to the damage degree of whole surfacing layer,then seting up fatigue cracking prediction models of steel deck pavement,and calculating the fatigue damage degree of practical bridge,forecast the of occurrence of fatigue cracking,and comparative analysis with the fatigue damage degree under standard axle load times,which is used to determine its rationality and accuracy.(5)Based on the developed fatigue shear test model,through comparing analysis of direct shear and compressive shear test,put forward the shear stress transformation equation which is thinking of sliding friction coefficient.Combined with shear fatigue test results under different conditions of temperature and stress level,shear fatigue equation under three temperature condition is established.Based on the analysis results of the maximum shear stress of asphalt pavement under different temperature and loading conditions,the maximum times of different axle loads in different temperature range is calculated.According to fatigue damage theory,the sum of damage degree at different actual axle loads conditions are used to the damage degree of whole surfacing layer,then seting up shear stress prediction models of steel deck pavement,and calculating the fatigue damage degree of practical bridge,forecast the of occurrence of shear stress,and comparative analysis with the fatigue damage degree under standard axle load times,which is used to determine its rationality and accuracy.(6)The shear stress of pavement material is determinded by using finite element analysis of steel bridge deck pavement composite structure,and the shear strength of pavement material is determinded by using triaxial test.On the basis of rutting test under different temperature and loading conditions,analysis of the relationship between rutting depth and frequency,temperature and shear performance parameters,then seting up rutting depth forecast modulus which is associated with these factors.At the same time,through the analysis of rutting depth deformation curve of different temperature and axle load,the two stage rutting depth prediction model is established,which can conduct the prediction calculation of cumulative deformation of the real bridge rut.Meanwhile,according to the measured rutting deformation data of the Ma'anshan Yangtze River Highway Bridge since the opening of the past years,the results are compared with the results of the prediction model.Based on the Maanshan Yangtze River Highway Bridge,structural damage prediction model of steel bridge deck pavement is built,which can predict the occurrence time of the fatigue cracking,shear delamination,rutting deformation and other structural damage and compare with the field test and analysis results.The prediction method proposed in this study is reasonable and scientific,which can be used to guide the steel deck of post operation and management and can also be set up for the key design index optimization of steel bridge deck pavement. |
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