POLYMERS

They are granulated products , a mixture of thermoplastic polymers , destined to asphalt modification. The polymers should be added directly into the mixer of the asphalt plant during the production faze. The bituminous conglomerates produced present a major stability and a higher resistance against deformation and mechanical stress ; therefore they find application on pavements for heavy traffic , under considerable static loads and on pavements requiring elevate physical and mechanical characteristics.

Modality of use
The grains are added directly into the blend system during the bituminous conglomerates production faze . Practically it is advice adding into the mixer first the aggregates and then the grains ; after 5 - 10 seconds of dry mixing can be added the bitumen and mix for 15 seconds; successively proceeds the over-mixing , normally for other 5 - 10 seconds.

Dosage
The dosage varies according to the final characteristics required by the bituminous conglomerate ; normally between 2% and 6% from the bitumen weight.

Packing
The products are delivered in bags 0f 500 kg and 1,000 kg. If required , they can be also delivered in plastic bags of 25 kg.

FIBRES

Adding the cellulose fibres to the bituminous conglomerate allows increasing the bitumen dosage and avoids the segregation and the leaking of it. Adding the metallic fibres to the bituminous conglomerate increases the stability and the mechanical resistance of the pavements. Both types of fibres are added during the production faze into the asphalt mixer.

Modality of use
The fibres are put into the blend system during the bituminous conglomerate mixing faze.

Dosage
The dosage varies according to the final characteristics required by the bituminous conglomerate. The average dosage for cellulose fibres is from 0,2% to 0,5% from the aggregate weight and between 2% and 5% from the aggregate weight , for metallic fibres.

Packing
They are delivered in bags of 500 kg. If required , can be used plastic bags of 3 kg for the cellulose fibres and of 25 kg for the metallic fibres.

CHEMICAL MODIFIERS

They are additives based on polyphosphoric acids for bitumen modification. The bitumen will present better reological properties , a higher softening point and a lower penetration.

Modality of use
The chemical modifiers are added to bitumen in heated and shacked mixers. The temperatures of work depend on bitumen type : usually between 160 - 170°C, and mixed for approximately 30 minutes.

Dosage
The dosage varies according to the chemical characteristics of the bitumen , normally from 0,3% to 2,0% from the bitumen weight.

Packing
They are delivered in 200 litre plastic drums or 1,000 litre IBC tanks. If required , in bulk from the tankers.