Asphalt mixture behavior in repeated flexure

Abstract

CONSIDERABLE INFORMATION HAS BEEN DEVELOPED ON THE FACTORS AFFECTING THE FATIGUE RESPONSE OF MIXTURES REPRESENTATIVE OF THE TYPE USED IN CALIFORNIA AND AN ATTEMPT HAS BEEN MADE TO SUMMARIZE THESE RESULTS INTO A FORM USABLE FOR DESIGN PURPOSES. THE INVESTIGATION HAS ALSO BEEN CONCERNED WITH THE DEFINITION OF A SUBSYSTEM TO CONSIDER THE FATIGUE MODE OF DISTRESS IN THE STRUCTURAL DESIGN OF NEW PAVEMENTS AND IN THE ANALYSIS OF EXISTING PAVEMENTS. GENERAL CONSIDERATIONS FOR THIS SUBSYSTEM HAVE BEEN SUMMARIZED AND THE MOST RECENT DEVELOPMENTS REQUIRED TO USE THE SUBSYSTEM HAVE BEEN INCLUDED TO MAKE THE PROCESS AS REALISTIC AND REASONABLE FOR ENGINEERING USE AS PRACTICABLE. FINALLY, IN ORDER THAT CONSIDERATIONS OF FATIGUE MAY EVENTUALLY BE INCORPORATED IN ASPHALT MIXTURE DESIGN REQUIREMENTS, A BRIEF DISCUSSION IS INCLUDED OF ALTERNATIVE WAYS IN WHICH FATIGUE RESPONSE MIGHT BE CONTROLLED OR DEFINED THROUGH A DIRECT TENSION TEST, A TEST WHICH IS MUCH LESS TIME CONSUMING AND SIMPLER TO PERFORM THAN CONVENTIONAL FATIGUE TESTS. /FHWA/