CEMENT-TREATED CRUSHED ROCK PAVEMENT FATIGUE UNDER ACCELERATED LOADING: THE MULGRAVE (VICTORIA) ALF TRIAL, 1989/1991

Abstract

This report describes the recent Accelerated Loading Facility (ALF) trial conducted in Australia on cement-treated crushed rock (CTCR) base pavements of two nominal thicknesses, 140 mm and 180 mm. The aim of the trial was to investigate their fatigue performance. A parallel laboratory and field testing program was conducted to complement the ALF trial. Fatigue relationships for cemented materials were derived. These relationships were compared to current Australian and overseas relationships. The modulus was found to decrease markedly with increase in the number of loading cycles well before surface cracking was apparent. Because of this, separate fatigue relationships are proposed for modelling pavements with more than 100 mm cover over cement materials from those with less than 100 mm cover. It is recommended that the Mulgrave relationships be used in a revision of the AUSTROADS Pavement Design Guide. As there is some doubt about the dependence of fatigue life on modulus, it is also recommended that a laboratory research program be undertaken to evaluate the effect of the modulus of cemented materials on fatigue life.