A COMPREHENSIVE RESEARCH ON LABORATORY PERFORMANCE OF ORGANOSILANE ADDITIVE IN BITUMINOUS MIX

Abstract

Investigations have been carried out in India and countries abroad to find out the properties of bitumen and bituminous mixes and by the methods by which they can be improved to cope up with the above defects of pavements and with the incorporation of certain additives or blend of additives. These additives that are added to enhance the binders are called “Bitumen Modifiers” and the bitumen premixed with these modifiers is known as “Modified Bitumen”. Modified bitumen’s performance depends upon the degree of modifications and type of additives and modification process used. The time period of next renewal is expected to extend by 50 per cent in case of surfacing with modified bitumen as compared to normal period indicated for conventional bitumen. For example, if normal renewal cycle is 4 years, this may be enhanced to 6 years in case of modified bitumen. Full scale performance studies carried out under the ages of Ministry of Road Transport and Highways, New Delhi, Central Road Research Institute , New Delhi , Highway Research Station, Chennai, Rubber Board, Kottayam, Gujarat Engineering Research Institute, Vadodara and Kerala Public Works Department revealed that the use of Modified Bitumen in construction/ maintenance of bituminous roads is cost effective, when life cycle cost is taken into consideration. The choice will in nut shell depend ultimately upon life cycle costing of overlays and renewals using ordinary bitumen and modified bitumen for prevailing traffic and climatic conditions. It will also depend upon the type of the pavement constructed. The need for bituminous binders has aroused due to the pavement failures. Pavement failures are one of the important issues in the entire pavement system. The failure can be due to a lot of issues, such as:
Defects of the materials used
Defects in the construction method
Defects in quality control during construction
Inadequate surface or sub surface drainage
Increase in magnitude of wheel loads and the number of load repetitions due to increase in traffic volume