A REVIEW ON STONE MATRIX ASPHALT BY USING STABILIZING ADDITIVES
Keywords:
Binder, Drain down, Flow, Mineral filler, Natural fibers, Stone matrix asphalt, Stabilizing additive.Abstract
The advanced technology of materials which is used in asphalt mixtures is developed in some countries like Europe and North America. The SMA (stone matrix asphalt) mixture is a gap graded open bituminous mixture which consists of high proportion of coarse aggregates, less medium sized aggregates with mineral filler and high binder content with low air voids. It resists permanent deformation and has the potential for long term performance and durability. The durability is provided by rich mortar binder. The flow and mechanical properties of the mix areto check the suitability of natural fibers as stabilizing agent in the mixture. The Stabilizing additives which includes fibers, polymers or waste materials in SMA mixture areused to stiffen the mastic at high temperature by reducing the asphalt drain down. This study compares the strength of pavement wearing course made with SMA mix without and
with different fibers.The Optimum Fiber Length of 6 to 8mm was found at Fiber Content of 0.3%. The SMA mix with Nominal maximum aggregate size shows better performance without using the stabilizing additive.The Stability and Bulk density are high for coconut fiber when compared with other fibers. Natural fibers shows better performance for preventing asphalt drain down compared to the polymer fibers.
