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The data show that 90/130 polymer modified binding material features conditional viscosity 1.7 times higher than that of more viscous 60/90 bitumen (table 3), whereas Трof the asphalt binding material is higher by 9°C and 11°C respectfully.
Table 3. Thermal stability and viscosity of bitumen, polymer
modified and asphalt binding materials
|
Sample |
Penetration at 25 °C, 0.1 mm |
Softening temperature, °С |
Viscosity, at 60°С, с |
| Bitumen БНД 60/90 + mineral powder |
– |
73 |
– |
| 60/90 bitumen |
68 |
49 |
603 |
| 90/130 PMB + mineral powder |
– |
84 |
– |
| 90/130PMB |
105 |
58 |
1054 |
Table4. Parameters
of flexibility, viscosity and plasticity of asphalt binding material based on
bitumen and PMB at 50°С
|
Parameter |
60/90 bitumen |
90/130PMB |
| Highest Newtonian viscosityη0 10-4, |
8.5 |
54.0 |
| Lowest plastic viscosityηm 101, |
4.9 |
23.7 |
| Dynamic (Bingham) yield point at shear, РK2, Pa |
4.4 |
24.0 |
| Equilibrium modulus of elasticity Gm, Pa at Р<РK2 |
139 |
463 |
| Stress relaxation period η0/Gm, sec |
611 |
1166 |
Analysis of rheological performance shows, that viscosity and elasticity of asphalt binding material based on 90/130 PMB is higher by a factor of 5 to 6 than that based on 60/90 bitumen, and strength is higher by a factor of 3.
This data indicate much higher shear strength of polymer asphalt concrete as compared to asphalt concrete; the data is confirmed by more than 9 year of polymer asphalt road top of Moscow Beltway.
Fatigue properties of the material are essential for its durability.
William Vonk of Shell tested fatigue properties of polymer asphalt concrete based on 90/130 PMB with 3.5% Kraton D 1101 block copolymer type SBS and 9% industrial oil, PMB with 5% of Kraton D 1101 with no plasticizer made by Shell and asphalt concrete based on B 80 heavy bitumen (figure 4).
The tests were run with constant deformation amplitude, which is the most representative of road operation conditions.
The data shows that the number of cycles to destruction of test beam with 90/130 PMB is higher by one order of magnitude than that of asphalt concrete and PMB asphalt concrete with no plasticizer.
In the same laboratory, Vonk determined the correlation between the maximum Newtonian viscosity of binders (bitumens and PMB) and rutting of asphalt concretes and polymer asphalt concrete of equal density.
Strain Vergelijk
Soyuzdorni en B80
1 – Soyuzdorni 10 °C; 2 – Soyuzdorni 20 °C; 3 – B80 blanco 10 °C; 4 – B80 + 5%D – 1101 10 °C; 5 – B80 + 5%D – 1101 20 °C
