Study On The Graded Crushed Stone Base Preventing Reflective Cracks Of The Asphalt Pavement

In order to study the applicability and inhibit the ability of reflection cracking of the graded crushed stone material under the light traffic loads, relying on the engineering background of Fushun Baoshang line test road, by the method of doing the indoor test, calculation and analysis pavement structure in theory and test road paving and testing. First of all, test the raw material physical and mechanical properties of graded crushed stone material inspection. Then, test the modulus of resilience and the CBR value of graded crushed stone material. Again design and calculate the pavement structure layer by HPDS pavement calculation software. Using FLAC3D numerical simulation software according to the design of structure layer on the theoretical analysis, which provide theoretical basis for the test road paving.Then design the test road according to the structure layer are done and test the grading of crushed stone road, including the test of grading macadam material compaction, modulus of resilience, CBR value, deflection value and other important technical indicators. After a period of time, test the flatness and fracture in view of the late of the road. Through the test and analysis, the modulus of resilience of graded crushed stone material, CBR value, deflection value and various technical indexes meet the design targets of subgrade material in highway subgrade design specification requirements, does not appear because of its flexible stiffness to lead to produce too much deformation of asphalt pavement. This proves that the graded crushed stone material as flexible base on joining between asphalt layer and the typical semi-rigid subgrade applicability. Then through observation the health status of the graded gravel road better than typical semi-rigid base asphalt road surface of the structure, thus directly proved that graded crushed stone material to prevent the produce reflective crack of asphalt pavement. Finally can be judged through the analysis of the economic benefits of grading macadam material economic applicability. In conclusion, because of the graded crushed stone material can improve existing prone to the phenomenon of reflection crack, so the idea macadam material as flexible base on pavement structure should be widely used in highway construction.