Comparative Study of RTFOT and PAV Aging Simulation Laboratory Tests

Tests were performed on unmodified asphalts of 35/50 grade penetration produced by French refineries to determine whether a prolonged pressure aging vessel (PAV) test would provide similar results to those obtained using the Strategic Highway Research Program coupled aging procedure, rolling thin film oven test (RTFOT) and PAV. Asphalts subjected only to PAV tests and identical samples after RTFOT and increasing PAV time were compared on the basis of ( a) conventional consistency tests, penetration at 25°C, ring and ball softening temperature; ( b) asphaltene content; ( c) creep rheological tests at low temperature with the bending beam rheometer; and ( d) complex modulus tests with the Metravib dynamic rheometer. The results show that a hypothesis of equivalence between the effects of ( a) RTFOT and 5 h of PAV aging at 100°C and under 2.1 MPa and ( b) RTFOT + 20 h of PAV and 25 h of PAV under the same conditions seems acceptable for the category of asphalts investigated.