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Deformability of asphalt concrete and polymer asphalt concrete was tested with both static and dynamic loads.
Polymer asphalt concrete has higher deformability at –20°C than asphalt concrete with bitumen, including thin bitumen; it has higher thermal resistance and elasticity at 20°C with both long and short load duration (see table below).
Table2.
Properties of sand based polymer asphalt concrete type D
|
Parameter |
Load time, seconds |
Temperature, °C |
Binding material |
|||
|
Original bitumen |
Thin bitumen |
Polymer modified bitumen with 2% polymer |
Polymer modified bitumen with 5% polymer |
|||
| Equilibrium modulus |
– – |
+20 -20 |
1,09 36,5 |
0,77 8,5 |
1,57 5,92 |
3,13 19,5 |
| Modulus of deformation |
10 0,02 |
+20 -20 -20 |
0,24 18,3 133 |
0,16 4,7 32,5 |
0,36 3,4 22 |
0,96 9,4 50,5 |
| PlasticityP |
– – |
+20 -20 |
0,34 0,151 |
0,39 0,147 |
0,34 0,142 |
0,28 0,107 |
| Highest viscosity of conditionally intact structure
– |
– – |
+20 -20 – |
11,6 488 42 |
7,6 270 35 |
15,6 340 22 |
31,2 1300 42 |
| Aging coefficientα befire aging αafter aging |
– |
-20 |
1,76 |
1,73 |
1,39 |
– |
Tests performed with a mechanical press by applying dynamic bending (piston movement 1200 mm per minute) show, that the temperature of brittle fracture of asphalt concrete does in fact shift significantly into the sub-zero range (by 20°C with optimal content of polymer, see figure below).
Also, flexing strength of polymer modified asphalt concrete at positive temperatures is higher than that of regular asphalt concrete.
The tests were performed both in sinusoidal mode in frequency range of 0.1 – 100Hz and in static flexing mode.
