Research On Performance Micrometer Based On Heavy Traffic

With the development of the national economy and highway transportation,the proportion of large-scale freight vehicles in transportation vehicles is increasing,the overload phenomenon is serious,the service life of asphalt pavement is greatly shortened,and preventive maintenance can not only improve the quality of road service,but also Extend the service life of asphalt pavement.Preventive maintenance is represented by micro-surfacing,which is widely used in China,but the conventional micro-surfacing has loose and easy-to-crack defects,and there is still a lack of deep understanding of the structural behavior mechanism of the micro-surfacing.In this paper,we will focus on the mechanical behavior and material design of micro-surfacing at the micro-surface under the heavy-duty traffic stress,and focus on the mechanical response of the micro-surface under heavy load.The structure and material design of the sealing layer provide a theoretical basis,and a high-performance micrometer is prepared by optimizing the grading design and fiber type at the micro-table.Firstly,through the ABAQUS finite element software,the two mechanical methods of statics and dynamics are used to calculate the mechanical response of the seal at the static surface,the average speed and the emergency braking.The sealing layer of the micro-surface is subjected to three-direction compressive stress under the action of static load,and the bottom of the layer is sheared.Both compressive and shear stresses increase significantly with increasing axle load.Under the action of average speed load,the micro-surface will be subjected to the stress alternating between tension and compression.Because of the fatigue damage caused by the seal at the micro-surfacing,under the emergency braking,the shear stress received by the micro-surface is the largest,reaching 80 KPa.The main factors of shear failure of the layer should be high-quality anti-cracking additives in design,and the friction coefficient on the surface of the micro-surfacing should be prevented from being too large.Three types of MS-3 micrometers were selected as design grading.Based on the road performance test results of micrometers,it was found that the wear resistance,water resistance and cohesion performance of grading A were superior to those of the other two grades.And the open alternate time is faster.The research shows that the structural depth and friction coefficient of the A-grade can meet the requirements of the handover.By adding fiber to further improve the durability of the micro-surfacing,andcomparing the improvement effect of the polypropylene fiber and the basalt fiber on the mixture,it was found that the improved performance of the polypropylene fiber was better than that of the basalt fiber,and the elongation at break was larger,and it was confirmed.The optimum blending amount of polypropylene fiber is 1%,and the optimum oil-stone ratio at the fiber micro-table is 6.5%-7.0%.