Research On The Fatigue Performance Of The Typical Asphalt Concrete From Semi-rigid Base Longlife Asphalt Pavement

Longlife asphalt pavement is an international hot issue of the research onthe pavement and asphalt pavement with semi-rigid base is the most typicalstructural form in China. It’s an important target to build longlife asphaltpavement with semi-rigid base after summing up valuable experiences at homeand abroad. It’s a key to research on the fatigue performance of the typicalmaterials to make sure they can meet the need of the longlife pavement.The unconfined compressive strength and compressive modulus ofresilience are used to analyze the effect of asphalt types, gradations and normalmaximum sizes on the mechanical property of the SAC series asphaltconcretes.It provides a basis to evaluate the SAC series fatigue performanceafter the equations between the volume/material parameter and mixtureperformance are established.After some analysis about the effect of different test methods, fatiguefailure criterias, life prediction equations on the evaluation of the fatigueperformance of the asphalt concrete, four-point bending fatigue tests areconducted to evaluate the fatigue performance in various ways. The endurancelimits of the typical materials are raised and they are checked whether theycould satisfy the requirement by the BISAR analysis software.Besides, a timely temperature-strain acquisition system is developed tomeasure the coefficient of linear contraction. At the same time, fatigueequations are corrected by the temperature based on the principle ofsuperposition of temperature shrinkage strain and tensile strain.