Degrading Performance Research Of OGFC Pavement On Vehicle Exhaust

In recent years, the fog weather happened frequently, more and more people are concerned about the air quality. Vehicle emissions are the main cause of air pollution. From the perspective of road engineering, the author studied that the performance of asphalt mixture degraded vehicle exhaust, based on the OGFC mixture add the photocatalytic materials.This paper mainly studied the evaluation method of asphalt mixturesbased on photocatalytic materials and the application methods of photocatalytic materials and the influence of different factors on the degradation of the exhaust.The author chose the factors that may affect the degradation of exhaust, such as the graded of Asphalt mixture, the voids of mixtures, the amount of photocatalytic materials, the degradation time and the light intensity. This paper designs the asphalt mixture of the OGFC-13 and OGFC-16, each type OGFC were designed three different void ratio, and each performance index of OGFC mixture was evaluated. Studies have shown that pavement performance of OGFC will decrease with increasing of voids, but all meet the requirements of specification.The author researched the effect of degradation of part of the exhaust component,such as CO, HC, NO and CO2, to achieve the evaluation of the effect of pavement materials for exhaust degradation, This paper designs the system to simulate that pavement degraded vehicle exhaust. The system includes airtight reaction device, produce exhaust equipment, the concentration of exhaust in real-time tester, wherein the airtight reaction device is the core of the system. According to the characteristics of degradation test system, developed the test methods includes controling the initial concentration of exhaust, simulating the degradation process, in real time measurement the concentration of exhaust and data collection and processing, etc. Put forward the degradation rate as evaluation index of performance of exhaus degradation, and give relevant formulas.The author chose the titanium dioxide as photocatalytic materials and analysis its catalytic mechanism. This paper studies the application method of titanium dioxide using in the asphalt mixture, putting forward spreading rolling, direct mixing, and equal volume of substitution. Studies shown that after spreading rolling method molding mixture the titanium dioxide easy to fall off, its durability is poor. Nano Ti O2 mixing to mixture make the void ratio reduced ignificantly, Application methods such as volume substitution had little effect on mixture performance, Performance degradation of NO and HC were more than 50% and 27%. Considering the degradation performance and road performance,finally,we selected the methods of equal volume of substitution.Using the reaction vessel and evaluation methods to study the effects of various factors on the performanceof degradation exhaust.The results shown that: OGFC-13 and OGFC-16 effect on the degradation exhaust or less, degradation rate of NO and HC respectively over 60% and 30%, degradation performance of OGFC was higher than the degradation performance of AC asphalt. Under the same other conditions, with the mix void ratio increasing, the degradation rate of the exhaust gas was gradually increased, but the increase marginally, Considering the road performance and exhaust degradation, recommend the best porosity of 21%. With the increase of the amount of photocatalytic materials, exhaust degradation effect is more obvious, Consider the economic and functional, This article select the amount of titanium dioxide slag is 50%. With the increase of the test of time extension and intensity of UV irradiation, and based on nano-Ti O2 OGFC mix of car exhaust degradation better.