Structure Analysis & Meterial Optimization For Concrete Beam Bridge Asphalt Mixture Deck

According to the problems of cracking, lapse, rutting exist in asphalt concrete beam bridge deck, this paper takes simply supported hollow slab of asphalt concrete pavement as the research object. Based on the theory of elasticity finite element method, using ANSYS, LSDYNA and other software to establish the finite element analysis model of the concrete beam bridge asphalt bridge deck, using radial tire to load entities, On the basis of analyzing statics, dynamics, and temperature response of the structure of the composite bridge deck, this article discusses the design method of the structure of the bridge deck asphalt concrete. By combining with the project in Guangdong Province, the material composition of hollow slab of asphalt concrete pavement is optimized and a test road is paved.Researches in this paper show that force of concrete beam bridge asphalt bridge deck structure is different from that of the ordinary road, the stress of the upper asphalt concrete pavement which contacts with the tire is the largest and the region has tendency of cracking from top to bottom, so by increasing the thickness of the upper asphalt concrete pavement appropriately and improving the adhesion properties of the interlayer the stress state of structure the can be enhanced effectively. The huge impact force generated by passing vehicle can easily causes damage near the pavement joints. When braking or on the longitudinal slope, the horizontal force generated by tire mainly acts on the upper asphalt concrete pavement, so it has a higher requirement for the antishear ability of asphalt concrete of the upper asphalt concrete bridge deck. At the same time, the temperature effect of concrete beam bridge deck can't be ignored, because the temperature stress is the main reason that causes the tearing and cracking of pavement edge. The temperaturevehicle load coupling function aggravates the destruction of the composite bridge deck.After the analysis of mechanics model, this paper discusses the design method of the asphalt concrete bridge deck structure and proposes asphalt concrete pavement surface maximum tensile stress as the main indicators of structural design, and maximum shear stress of asphalt concrete as the auxiliary indicators, and the main flow of asphalt concrete pavement structure design is also proposed. By using multilevel embedded antishear grading design method to optimize the gradation, and the lower and upper pavement asphalt mixture is designed based on layer functions. Glass fiber reinforced asphalt concrete is recommended to use in this paper, through the comparison test in the mechanical properties before and after asphalt concrete deck by mixing glass fibers, it can be known that the glass fiber had an improvement on the mechanical performance in the lower and the upper deck, can effectively improve the tensile strength, shear and fatigue properties of asphalt mixture, make the deck adapt to the force characteristics, at the same time, this paper deeply analyzed four different mechanical bonding layer waterproof and performance, recommended engineering to use it.