Variability And Influence Analysis Of Aggregate Performance Of Asphalt Pavement In Tianjin Area

Semi rigid base as a highway pavement structure type is widely used on expressways in Tianjin.Tianjin has a hot and rainy summer climate,a large traffic volume and a large proportion of trucks,which requires high performance of asphalt mixture.However,there is no material source in Tianjin area.All the stone materials needed are purchased from neighboring provinces,including Hebei Province and Shandong Province.The material sources are more complex,the aggregate differences are greater,and the aggregate quality is difficult to control.The current code does not provide the standard of aggregate technology suitable for the region in light of the characteristics of Tianjin.This paper investigates three kinds of aggregates used by seven construction units in Tianjin,such as coarse aggregate,fine aggregate and mineral powder.According to the characteristics of aggregate source and processing characteristics,the design experiments are carried out: according to the characteristics of aggregate source,using the research results of Jiangsu and Shandong Province for reference,the quality control is achieved by improving the key indicators which have a greater impact on the road performance of asphalt mixture;according to the processing characteristics of aggregate indicators.Laboratory test,mainly from the particle composition variability,angularity and cleanliness analysis to add new coarse aggregate,fine aggregate technical indicators,but also on the impact of recycled powder on the mineral powder analysis,put forward the corresponding requirements after performance verification.Afterwards,different aggregate combinations are used to carry out laboratory tests,and the pavement performance of asphalt mixture is analyzed and evaluated,so as to put forward the aggregate technical requirements for Tianjin Expressway Asphalt pavement.