Crumb rubber of particles ranging in size from 4. 75 mm (No. 4 sieve) to less than 0. 075 mm (No. 200 sieve) .
All over the world billions of scrap tires are processed into ground rubber annually. Ground tire rubber is used in rubber products (such as floor mats, carpet padding, and vehicle mud guards), plastic products, and as a fine aggregate addition (dry process) in asphalt friction courses. Crumb rubber has been used as an asphalt binder modifier (wet process) in hot mix asphalt pavements.
Now we are planning to introduce this technology in Kingdom of Saudi Arabia for the first time.
Our products would be
150-300 mm rubber shreds ( as per costumer needs)
20 mm rubber chips
1-7 mm granulated crumb rubber (Best for Rubberize Asphalt , Asphaltic concrete and other construction materials)
Mainly our product can be utilized as:
HIGHWAY USES AND PROCESSING REQUIREMENTS
Embankment Construction - Shredded or Chipped Tires
Shredded or chipped tires have been used as a lightweight fill material for construction of embankments.
Aggregate Substitute - Ground Rubber
Ground rubber has been used as a fine aggregate substitute in asphalt pavements. In this process, ground rubber particles are added into the hot mix as a fine aggregate in a gap-graded friction course type of mixture. This process, commonly referred to as the dry process, typically uses ground rubber particles ranging from approximately 6.4 mm (1/4 in) down to 0.85 mm (No. 20 sieve).(4) Asphalt mixes in which ground rubber particles are added as a portion of the fine aggregate are referred to as rubberized asphalt.
Asphalt Modifier - Crumb Rubber
Crumb rubber can be used to modify the asphalt binder (e.g., increase its viscosity) in a process in which the rubber is blended with asphalt binder (usually in the range of 18 to 25 percent rubber). This process, commonly referred to as the wet process, blends and partially reacts crumb rubber with asphalt cement at high temperatures to produce a rubberized asphalt binder. Most of the wet processes require crumb rubber particles between 0.6 mm (No. 30 sieve) and 0.15 mm (No. 100 sieve) in size. The modified binder is commonly referred to as asphalt-rubber.
Asphalt-rubber binders are used primarily in hot mix asphalt paving, but are also used in seal coat applications as a stress absorbing membrane (SAM), a stress absorbing membrane interlayer (SAMI), or as a membrane sealant without any aggregate.
Properties of our products
Tire chips are more finely and uniformly sized, ranging from 76 mm (3 in) down to approximately 13 mm (1/2 in) in size. Although the size of tire chips, varies with the make and condition of the processing equipment, nearly all tire chip particles can be gravel sized. The loose density of tire chips can be expected to range from 320 kg/m3 (20 lb/ft3) to 490 kg/m3 (30 lb/ft3). The compacted density of tire chips probably ranges from 570 kg/m3 (35 lb/ft3) to 730 kg/m3 (45 lb/ft3).(9) Tire chips have absorption values that range from 2.0 to 3.8 percent.
Ground rubber particles are intermediate in size between tire chips and crumb rubber. The particle sizing of ground rubber ranges from 9.5 mm (3/8 in) to 0.85 mm (No. 20 sieve).
Crumb rubber used in hot mix asphalt normally has 100 percent of the particles finer than 4.75 mm (No. 4 sieve). Although the majority of the particles used in the wet process are sized within the 1.2 mm (No. 16 sieve) to 0.42 mm (No. 40 sieve) range, some crumb rubber particles may be as fine as 0.075 mm (No. 200 sieve). The specific gravity of crumb rubber is approximately 1.15, and the product must be free of fabric, wire, or other contaminants.
Tire chips and tire shreds are nonreactive under normal environmental conditions. The principal chemical component of tires is a blend of natural and synthetic rubber, but additional components include carbon black, sulfur, polymers, oil, paraffins, pigments, fabrics, and bead or belt materials.
The shear strength characteristics of tire chips vary according to the size and shape of the chips, internal friction angles were found to range from 19o to 26o, while cohesion values ranged from 4.3 kPa (90 lb/ft2) to 11.5 kPa (90 to 240 lb/ft2). Tire chips have a permeability coefficient ranging from 1.5 to 15 cm/sec.
Tire chips can also be expected to exhibit high insulating properties. If tire chips are used as a fill material in subgrade applications, reduced depth of frost penetration compared with that of granular soil can be expected.
Benifits For Road Manufacturers
Easier, faster and more uniform mixing
Densities achieved with less rolling, and only requires static rollers
Superior surface finish
Application at low road-surface temperatures
Reduced cracking and rutting
Longer serviceable pavement life
Eliminate terminal bleeding
Lower cost per mile (blend with a lower grade of asphalt cement, thinner mats)
Thermally stable at 520ºF
Melting point 130ºF
From laboratory tests its proven now, using rubberize Asphaltic concrete instead of using normal asphaltic concrete boost up the efficiency and life of roads and pavements.