Details of fiberglass geogrid
2, anti fatigue crackIn the old cement concrete pavement asphalt overlay, its main function is to improve the use function of the road, and the contribution to the bearing capacity is not big. The asphalt overlay on the old asphalt concrete pavement is different, and the asphalt overlay will be combined with the old asphalt concrete pavement. Therefore, the asphalt overlay on asphalt concrete pavement, in addition to the emergence of reflective cracks, but also because of the long-term effects of fatigue cracks. We overlay load do stress analysis of old asphalt concrete pavement and the asphalt because of asphalt overlays under flexible surface cover layer of the same nature and the asphalt surface, when subjected to loads, road surface deflection will occur. The surface layer under pressure in direct contact with the wheel of the wheel load in asphalt overlay, the outside edge of the area, the surface layer by force, due to the two force regional force are different in nature, and close to each other, so in the junction of two force area is prone to damage force mutation. Fatigue cracking occurs under the action of long term loads.Fiberglass geogrid in bituminous surface layer, to the compressive stress and tensile stress dispersion in the two block of stress region is formed between the buffer zone, where the stress gradually changes instead of mutation, reduces the stress mutation on asphalt surface damage. At the same time, the low elongation of fiberglass geogrid reduces the deflection of pavement, which ensures that the pavement will not be deformed.
1, slow down reflection crackThe reflection crack is due to the old concrete surface layer in the vicinity of the joint or crack of large displacement caused by asphalt overlay in above the stress concentration caused by it, including horizontal displacement caused by changes in temperature and humidity, and caused by the traffic load of the vertical shear displacement. The former leads to the concentrated tensile stress in the asphalt overlay above the joint or crack, while the latter makes the asphalt overlay above the joint undergo large bending stress and shear stress.Because the modulus of geogrid is very large, up to 67Gpa, as the application of hard interlayer stiffness in asphalt overlay layer, its role is to inhibit stress, strain release, and at the same time as the asphalt concrete reinforced material, improve overlay tensile and shear capacity, so as to achieve the purpose of crack reduction. Practice shows that a change in the direction of the horizontal crack corresponding energy can be moved from its starting point 0.6 meters, more than 1.5 meters width of the reinforcement material helps to ensure that the energy dissipated on both sides of the crack completely.
3, high temperature rutThe asphalt concrete has rheological properties at high temperature, specific performance in summer: asphalt road surface soft and sticky; under the vehicle load, the stress area from depression, vehicle load after the removal of the asphalt surface layer cannot be completely restored to the loading condition before, which produce plastic deformation in the vehicle repeatedly; under the action of rolling plastic deformation accumulation, rutting. We analyze the asphalt pavement structure, because of high temperature asphalt concrete with rheology, while under load, without any constraint mechanism can aggregate movement of the asphalt concrete surface layer, resulting in asphalt surface layer goes on, this is the main reason of the formation of rutting.The fiberglass geogrid is used in the asphalt overlay, which plays the role of skeleton in the asphalt surface layer. The asphalt concrete aggregate throughout the grid, to form a composite mechanical interlocking system, limit the aggregate movement, increase the lateral cover surface layer in asphalt binding, each part of the asphalt layer in each other, to prevent the asphalt surface layer goes on, which plays the role of rutting resistance.
