Crumb_Rubber_Modified_Bitum

MARUTI CRMB is special type of bitumen whose properties have been improved by the addition of crumb rubber & special types of additives like hydrocarbon materials, resins etc. Thus altering the physical properties of bitumen makes it more resistant to temperature variations, weather & high traffic loads, leading to enhanced pavement life, reduced maintenance cost and excellent driving comfort.

Applications

CRMB can be used for wearing courses at heavy trafficked roads, busy intersections, bridge decks and roundabouts for increased life of the surfacing.

  • Reducing traffic noise
  • Bus by lane
  • Water proofing concrete structure
  • Sand asphalt
  • Heaving traffic lane
  • Slopes, roundabouts, junctions
  • Industrial and multimodal platforms
  • Providing high skid resistance (thin overlay chip seal)
  • Porous asphalt and acoustic thin overlay
  • In Stress Absorbing Membrane Interlayer (SAMI)
  • For high rainfall regions
  • Airport runways and parking apron
  • Parking place of buses and trucks

Specifications

Mixing / Coating

170 – 185 °C

Laying

150 – 170 °C

Beginning of compaction

Over 140 °C

End of compaction

110 – 120 °C

No.

Designation

Grades & Requirements

Test Method

CRMB 50

CRMB 55

CRMB 60

1

Penetration at 25 °C

<70

<60

<50

IS 1203-1978

2

Softening point, ( R & B ), C Min.

50

55

60

IS 1205-1978

3

Elastic recovery of half thread in
Ductilometer at 15 °C, % Min.

50

50

50

IS 15462-2004

4

Flash point °C Min.

220

220

220

IS 1209-1978

5

Separation difference in softening
point, ( R & B ) °C Max.

4

4

4

IS 15462-2004

6

Thin Film Oven Test (TFOT) on residue

a). Penetration at 25 °C, Min. % of original

60

60

60

IS 1203 – 1978

b). Increase in softening point, °C Max.

7

6

5

IS 1205 – 1978

c). Elastic recovery of half thread in Ductilometer at 25 °C, % Min.

35

35

35

IS 15462 -2004

Advantages

  • Lower susceptibility to daily & seasonal temperature variations
  • Higher resistance to deformation at elevated pavement temperature
  • Better edge resistance properties
  • Better adhesion between aggregate & binder ensure longer life, strength & stability
  • Higher fatigue life of mixes due to high elastic recovery
  • Delay of cracking & reflective cracking
  • Overall improved performance in extreme climate conditions & under heavy traffic condition
  • Better water resistance
  • Prevents rutting
  • Resistance to creep & higher indirect tensile strengthen surface course

Types of CRMB & Recommendation for specific use:

  • CRMB 60: recommended for hot climate areas.
  • CRMB 55: recommended for moderate climate areas.
  • CRMB 50: recommended for cold climate areas.