THE EFFECT OF MIX VARIABLES ON THE FATIGUE STRENGTH OF BITUMINOUS MATERIALS

摘要: This report covers work carried out at the University of Nottingham from November 1968 to October 1972 on a contract awarded by Transport and Road Research Laboratory investigate effect mix variables fatigue properties bitumen- tar-bound road materials. Fatigue testing was in controlled stress rotating bending machines. Measurements dynamic stiffness were also made enable results be analysed basis applied strain. During four years testing, considerable number different mixes investigated under variety test conditions. Both basecourse wearing course gap graded continuously type used. The effects such as binder content, type, aggregate grading use filler studied. is divided into main sections. Firstly, method specimen manufacture presentation are described. Secondly, annual reports reviewed individually, indicating conclusions. Thirdly, roles various relation performance discussed. Finally, statistical analysis order determine most significant variables, proposing for prediction laboratory performance. conclusions that strain primarily influenced volume content type. Binder appears conveniently represented an equiviscous temperature region ring ball softening point. other apparently accounted their mix, only when relative affected do these factors indirectly influence It shown can reasonably predicted using merely binder. /Author/ /TRRL/