Experimental Study on Micro Surfacing using Chrome Shaving Impregnated with Modified Bitumen Emulsion

摘要

It has been stated that about 600,000 tones of solid waste is being generated worldwide by the leather industry in which 40-50% of the hides are lost due to shavings and trimmings. Basic Trivalent Chromium (Cr (Ⅲ)) sulfate is widely used as tannage material. Only 60-80% of the total Chromium (Cr) reacts with the hides and about 20-40% of the total Cr remains un-reacted in the liquor. Chrome shavings (CS) are the scrap generated during leveling of tanned skins, and mainly consisting of collagen cross linked with Cr (Ⅲ). As of now, there are insufficient report and researches on the use of leather industry waste in bituminous mixes. This study focuses on the use of CS as filler in micro surfacing for pavement preservation, to overcome the burden of CS disposal. Micro surfacing is a mixture of dense - graded aggregate, polymer modified bitumen emulsion, mineral filler, and water. Therefore, in this study an experimental micro surfacing layer was laid on the heavy traffic road namely Sardar Patel Road, Chennai, Tamil Nadu, India, having more than 1500 CVPD (Type Ⅲ). Another experimental section was laid on a light traffic road with less than 1500 CVPD (Type Ⅱ) in the premises of Anna University, Chennai.