Penetration grade bitumen is a standard bitumen for road construction in various environmental conditions. Penetration test of Bitumen determines the hardness or softness of bitumen by measuring the depth in millimeter to which a standard loaded needle will penetrate vertically in five seconds while the temperature of the bitumen sample is maintained at 250C.
Also, the Penetration test is used to measure the consistency of bitumen. The penetration is measured to specify the bitumen type according to the climatic conditions of the area that bitumen consumed. This penetration depth is empirically correlated with asphalt binder performance. Therefore, asphalt binders with high penetration numbers (called “soft”) are used for cold climates (like 70/100) while asphalt binders with low penetration numbers (called “hard”) are used for warm climates (like 35/50).
| Property | 10/20 | 15/25 | 35/50 | 50/70 | 70/100 | 150/200 | Test Method |
|---|---|---|---|---|---|---|---|
| 1) Penetration at 25oC/100g/5s/1/10mm | 10-20 | 15-25 | 35-50 | 50-70 | 70-100 | 150-200 | EN 1426 |
| 2) Softening point (R&B), oC | 58-78 | 55-71 | 49-59 | 46-56 | 42-51 | 36-43 | ASTM D36 |
| 3) Viscosity at 60oC, Pa.s, Min | 700 | 550 | 220 | 120 | 75 | 30 | ASTM D 4402 |
| 4) Viscosity at 135oC, mPa.s | ≥ 750 | ≥ 650 | 270-700 | 220-500 | 150-400 | 120-300 | ASTM D 4402 |
| 5) Flash point, oC, Min. | 245 | 235 | 240 | 230 | 230 | 220 | ASTM D 92 |
| 6) Performance when subjected to the rollingthin film oven test: | ASTM D 2872 | ||||||
| a) Mass change, % (by mass fraction), Max. | - | 0,5 | 0,3 | 0,3 | 0,3 | 0,3 | ASTM D 2872 |
| b) Viscosity at 60oC, % of original, Max. | - | - | 300 | 300 | 300 | 300 | ASTM D 4402 |
| c) Softening point (R&B), oC Min. | - | 57 | 52 | 48 | 44 | 37 | ASTM D 36 |
| d) Increase in softening point, oC, Max. | 10 | 8 | 7 | 7 | 7 | 7 | ASTM D 36 |
| e) Retained penetration, % of original, Min. | - | 55 | 60 | 55 | 50 | 50 | EN 1426 |
| 7) Spot test, % xylene, Max. | - | - | 30 | 30 | 30 | 30 | AASHTO T 102 |
| 8) Typical density at various temperatures, kg/litre: | |||||||
| 25oC | - | - | 1,031 | 1,030 | 1,029 | 1,026 | ASTM D 3142/D 3142 M-11 |
| 135oC | - | - | 0,956 | 0,954 | 0,953 | 0,950 | ASTM D 3142/D 3142 M-11 |
| 160oC | - | - | 0,928 | 0,937 | 0,936 | 0,933 | ASTM D 3142/D 3142 M-11 |
| 175oC | - | - | 0,928 | 0,927 | 0,926 | 0,923 | ASTM D 3142/D 3142 M-11 |