Research On Quality Control Technology Of Asphalt Concrete Bridge Deck Pavement Of Expressway In Mountainous Area

In recent years,with the rapid development of society and national economy,the traffic demand is increasing,highway and bridge projects are increasing,the construction process is fast,and the rapid development has become the main characteristics of the current development of the transportation industry.With the continuous development of the transportation industry,highway bridges continue to be vigorously developed and constructed,and constantly put into production and operation,resulting in the early built highway bridges are bound to appear a variety of different diseases.The bridge of expressway is the difficulty and key point of construction,in which the bridge deck,as the concentrated outbreak area of disease,will always become the focus of the problem.The occurrence of bridge deck pavement disease of Expressway increases the operation cost of Expressway to a great extent,and affects the safety of driving.Therefore,it is necessary to control the quality of engineering construction,study the quality control technology of highway deck pavement,fundamentally reduce the occurrence of diseases,improve the service time of highway bridges,reduce the cost of the whole life cycle of the project,and reduce the cost of engineering maintenance,so as to improve the economic benefits of expressway bridges in the operation process.This paper takes the construction of Longnan section of Weiwu expressway as the research background,studies the mixture ratio of asphalt concrete bridge deck pavement and the physical performance index of composite structure.First of all,the early damage and disease causes of asphalt concrete bridge deck pavement structure are investigated and studied.It is found that in the initial stage of construction and use,there are mainly material reasons,and the related diseases include surface cracks,surface deformation,surface damage,adhesion and waterproof damage between layers.Secondly,the cause of the disease is analyzed,and the pavement structure is discussed from the physical and mechanical properties of the material.It is found that the main causes of the initial disease are that the stress condition of the bridge deck pavement does not match with the mechanical properties of the material,the calculation of the load is not complete,the bonding degree between the pavement layers is not enough,and the quality control of rawmaterials is insufficient.The results show that: the bond strength of waterproof layer has significant influence on the overall stress and deformation of the main structure of the pavement,and the quality of the waterproof adhesive layer directly determines the structural strength and durability of the highway deck pavement;the coarse aggregate of the upper layer of the asphalt concrete bridge deck pavement should be made of basic organic sand such as limestone and basalt,and the coarse aggregate of the lower layer should be limestone macadam;the fine aggregate should be alkali limestone manufactured sand;the upper layer asphalt should be SBS modified asphalt,the base asphalt should be 70# petroleum asphalt with the modifier content of 4%;the lower layer asphalt should be 70# petroleum modified asphalt;the mineral powder of asphalt mixture should be clean high-quality limestone powder as raw material.Finally,the paper studies the technical performance requirements of raw material performance of pavement construction,studies the mix proportion design of pavement asphalt mixture,and summarizes the control points of each link of asphalt construction.The results show that SMA-13 asphalt mixture with good fatigue resistance and low temperature shrinkage cracking performance should be used for the upper layer to meet the requirements of good rutting resistance,skid resistance and impermeability,and the porosity should be controlled between 3-4.5%;sup-20 asphalt mixture with good high temperature stability should be used for the lower layer,and the porosity should be controlled at 4%;in order to improve the shear and tensile properties of pavement waterproof and bonding materials,SBR modified emulsified asphalt with impermeability of 0.05 Mpa is used as the main bonding material of bridge pavement;the construction quality control of asphalt concrete bridge deck pavement should be carried out from the aspects of mixture mixing control,transportation control and construction control.