Engineering properties of warm mix asphalt using synthetic zeolite as an additive

Abstract

Warm mix asphalt(WMA) is a recent technology used to reduce the mixing and compactiontemperatures without affecting the quality of pavement. Warm mix asphalt is a bituminous mixture where all its constituents are mixed, placed, compacted at medium temperature .A number of WMA processes havebeen developed in recent days. One of the processes includes the use ofsynthetic zeolite as anadditive.An attempt has been made in the laboratory to develop warm mix asphalt mixes using synthetic zeolite asan additive at a specified mixing and compaction temperature which were obtained after a number of trials.Thestone matrix asphalt (SMA) and dense bituminous macadam (DBM)mixes with aggregate gradation as per MORTH specifications were made with varying bindercontents (5%,6% and7%). The zeolite content was 0.3% by weight of aggregate. Stone dust and cement were used as filler for SMA andDBM samples respectively. VG 30 grade bitumen was used as binder for both the mixes.Marshall procedure has been made for preparation of samples and evaluation of bituminous mixes. The volumetric properties (VA, VMA and VFB), stability, flow value and optimum binder content of the SMA and DBM mix samples have beeninvestigated. The optimum binder content ofthe DBM and SMA samples was found to be 5.3% and 5.8% respectively.