CRMB is bitumen modified by adding finely ground crumb rubber particles obtained from waste tires, producing a durable and flexible material with enhanced resistance to wear, tear, and weather conditions.

CRMB mainly consists of bitumen and crumb rubber derived from mechanically ground scrap truck and automobile tires. Some compositions may also include spent catalysts or additional polymers for enhanced properties.

The process involves heating bitumen, blending the crumb rubber at high temperatures (usually around 180°C), allowing swelling and digestion of rubber particles in bitumen, followed by mixing to ensure uniform dispersion and filtration to remove undissolved solids.

Crumb rubber particle size typically ranges from 0.6 to 0.8 mm, though it can vary from about 10 microns up to 2 mm depending on the process and product requirements.

CRMB improves elasticity, resistance to rutting and cracking, fatigue resistance, and durability of pavements. It also supports recycling of scrap tires, contributing to environmental sustainability.

Different grades of CRMB are recommended for varied climates, e.g., CRMB 60 for warm climates, CRMB 55 for moderate climates, and CRMB 50 for cold climates, optimizing pavement performance against temperature extremes.

By increasing binder elasticity and adhesion, CRMB reduces cracking and permanent deformation, doubling or extending the lifespan of road surfaces compared to conventional bitumen.

CRMB utilizes recycled tires, reducing landfill waste and providing an eco-friendly alternative to traditional bituminous binders.