Bitumen binders are used in flexible pavement construction. It is important for bituminous material to form ductile thin film around the aggregates, which serves as a binder. If the binder material does not have sufficient ductility, it leads to spurious pavement surface and leads to development of cracks. Therefore it is extremely important to carry out the ductility test on bituminous material.

Ductility is defined as distance in centimeters to which a standard briquette of bitumen can be stretched before the thread breaks.

Salient Features
The important features of ductility testing apparatus are :

• There is a water bath with a thermoplastic heater in the apparatus, along with a circulating pump to maintain uniform water temperature.
• One half of the briquette moulds is fixed on a fixed plate in the water bath, the other half of the briquette mould is fixed to a carrier, which slides over a rotating the threaded shaft with a clutch.
• The shaft is rotated by motors and gears and are encased in a cabinet that is fixed above the other end of the bath.
• There is a pointer, which is fixed to the carrier and moves over a scale graduated from 0-110 cm x 1 mm fixed on the bath with Zero of the scale towards the side of fixed plates.
• The rotating shaft has two speeds of travel for the bracket, 5 cm/minute and 1cm/minute, selected by a clutch.
• The water bath is insulated and inside of the water bath is made of aluminum or stainless steel. The water bath is provided with a drain.
• A thermostatic controlled heater is fixed inside the water bath.
• Control switches for indicator lamp and motor pump heater are fixed at a convenient place on the water bath.
• The complete apparatus is supplied with three briquette moulds and one base plate, all made of brass. They operate on 230 volts single phase A.C. supply.

Accessories of Ductility Testing Apparatus

• Thermometer IP 38 C, range 23º C to 27º C.
• Ductility mould with base-plate made of Gunmetal.

Applications

• Pavement & Highway Construction
• Building Construction
• Road Testing
• Research Laboratory
• Soil Study