Flexural and Cracking Behaviour of Roller Compacted Asphalt Concrete

Abstract

This work is intended to evaluate the flexural and cracking behavior of both Dense and Gap graded Asphalt concrete. Slab samples of 30×30×7cm size have been constructed in the laboratory using the TRRL roller wheel compactor. Various Asphalt percentages were adopted.Beams were sawed from the slabs at two different positions (parallel and perpendicular to rolling direction). Beams were tested for flexural strength at 8˚C and the load-deformation relationships were obtained. The flexural modulus, the stiffness and E- Modulus were determined. The deflection and cracking of beams were observed and the various modes of displacement were studied. It was concluded that rolling direction has a significant effect on fracture strength for both Dense and Gap graded Asphalt Concrete; The predicted displacement of beams with Gap gradation were higher especially at high Asphalt content when compared to Dense mixes while the variation of measured displacement between Dense and Gap mixes is not significant. E- Modulus of dense mixes was higher at various Asphalt percentages. On the other hand, the variation of both flexural and stiffness modulus at optimum Asphalt content was not significant for all of the mixes studied.