Study on grading envelope of AC-16 asphalt mixture based on rutting resistance performance
In this paper, the coarse aggregate packing density tests are studied on different proportion the various particle sizes over 4.75mm, and the demarcation point between coarse and fine aggregate of AC-16 asphalt mixture is 4.75mm, the optimum grading of coarse aggregate is determined by the minimum voids in mineral aggregate. Freeze-Thaw Split and Rutting are tested on 9 kinds of grading AC-16 asphalt mixture with different size and proportion fine aggregate. The results show that the percent passing 4.75mm sieve has affected significantly on the high-temperature rutting resistance and water stability of the asphalt mixture. Based on laboratory test results and grading application experience, it is proposed that the engineering design grading envelope of AC-16 asphalt mixture adapted to the summer hot climates characteristics, which improved the rutting resistance capability of asphalt pavement in hot areas during summer.
Study of Molding Control on Wheel Tracking Specimens for Asphalt Mixtures
The difference in terms of control index and standard of typical wheel tracking test specimen was reviewed.Test results of California HVS were also analyzed.Through analysis,it is found that field air void under track is no less than 4% after long-term vehicle loading.When asphalt pavements vary from field initial air voids to the air voids of the end of life,creep defor-(mation) mainly contributes the rut depth,while dense deformation contributes little.So the maximum expected field initial air voids are suggested as the specimen molding control index.At last,through tests and analysis,(7.0±1.0)% air void is suggested for dense-graded hot-mix asphalts as the molding control standard,and (5.5±0.5)% for stone matrix asphalts(SMA).
Second-Generation Process Research Towards Eletriptan: A Fischer Indole Approach
The development of a second-generation process for the synthesis of eletriptan via a Fischer indole cyclisation is described. The finalised process offers several potential advantages over the current route of manufacture including cost, throughput, and safety.