Study On Pavement Structural Form And Transverse Local Stiffness Of Orthotropic Steel Deck

In order to sort out the application and research status of steel deck pavement and recommend more reasonable pavement structure,this paper collates and compares the relevant specifications and requirements of steel deck pavement,investigates the pavement structure,temperature,deck stiffness of 114 steel bridges at home and abroad,analyzes the performance and combination mechanism of pavement materials,compares the calculation methods of deck stiffness,calculates and analyzes the actual bridge deck stiffness and strengthening measures,Finally,the technical characteristics and application prospects of various pavement structures are evaluated.In addition,in order to further study the transverse local stiffness of orthotropic steel deck,based on the analysis of the above-mentioned pavement application investigation,the finite element model of local beam section is established by using ABAQUS,and the strengthening measures of horizontal "l" shape,"l" shape and "H" shape suitable for orthotropic steel deck pavement system are proposed,and the structural parameter design and strengthening effect are comprehensively referred Based on the numerical analysis and regression fitting,the corresponding strengthening measures for the position without web and web are proposed.The main research contents and conclusions are as follows:(1)According to the investigation and analysis of pavement structure at home and abroad,the double-layer SMAM pavement structure is widely used before 2010,but its application status is mostly poor.At present,the more excellent schemes of steel deck pavement are doublelayer EAM,GAM + SMAM and ers,but due to the limitation of material properties,the service life of GAM and SMAM is difficult to further improve,and EAM has high cost and difficult to repair after damage Problem.(2)The setting of rigid base improves the stress condition of pavement and steel deck obviously,the cost of fiber concrete is low,so it has a good application prospect.UHPC has excellent performance but high cost,so it can be widely used only by further reducing the cost.In addition,the results of rigidity calculation of steel bridge deck with rigid base as permanent structure or pavement structure are obviously different.(3)Based on ABAQUS,the finite element model of local beam section is established,and the least load position and stress characteristics of steel bridge deck pavement are analyzed.Combined with the analysis of pavement application investigation,the strengthening measures of horizontal "l" shape,"l" shape and "H" shape are put forward.The single parameter analysis of horizontal "l" shape width,plate thickness,"l" shape height and plate thickness is carried out,and the results show that horizontal "l" shape strengthening measures have little improvement on the indexes of OSBD bridge deck system,the vertical shear rigidity of "l" shape strengthening measures is larger,and the improvement on the indexes of OSBD bridge deck system is obvious.(4)Based on the single parameter analysis results and basis of horizontal "l" shape and "l" shape,combined with the requirements of plate thickness ratio in the code,it is clear that the optimal scheme of strengthening measures should be "H" shape,and the maximum plate thickness ratio should be taken for the web height,and then the full-scale parameter analysis is made for the width of "H" shape roof and bottom plate,and the fitting formula and design suggestions are given.The research results show that "H" shape is the best choice for OSBD bridge deck system without web and web position,various indexes are significantly improved by the shape reinforcement measures,and many indexes are far better than the scheme of roof thickening.The improvement effect of tensile strain on the pavement surface is about 38%,and the improvement efficiency is 2.2 times of that of the roof thickening scheme;the reduction of shear stress between the steel roof and the pavement is 22.5%～26.2% respectively;the improvement effects of the maximum vertical displacement of the steel roof,the maximum vertical overall displacement and the transverse displacement between the two floors are 39.5%,57.4% and 75.1% respectively,and the improvement efficiency is relative to that of the roof thickening scheme The reduction of the stress in the through welded hole of diaphragm is 55.3% ～ 76.7%.