沥青混凝土材料的力学性能对车辙的影响分析

Effect of Mechanical Properties of Asphalt Concrete on Rutting

沥青混凝土材料是一种与温度、荷载和作用时间相关的黏弹塑性材料,其力学性指标直接影响路面使用性能。将日气温场引入沥青混凝土车辙计算模型,分别计算了温度、交通量、蠕变等参数对沥青混凝土面层的永久变形的影响。计算结果表明:沥青混凝土材料受温度和材料的蠕变性能影响巨大,要增强沥青混凝土的高温抗辙槽能力和高温蠕变性能;车辙随着交通量的增大其增速会放缓,要注重沥青混凝土路面初期的压实和嵌挤结构的形成;弹性参数对沥青混凝土路面辙槽的影响几乎可以忽略。不同路面结构形式的计算表明:路面结构的组合对沥青混凝土路面的车辙产生了重大的影响,上面层和中面层是永久变形的主要来源,选择高温蠕变性能优良的面层材料,尤其是上面层材料对降低车辙具有重要意义。

Asphalt concrete material is a viscoelastic plastic material related with temperature, load and time; its mechanical properties have direct influence on the asphalt concrete pavement. The temperature field was introduced into the rutting calculation model of asphalt concrete, and the effect of temperature, traffic volume and creep parameters on the permanent deformation of asphalt concrete layer of was calculated respectively. The calculation results show that, the asphalt concrete materials are hugely influenced by creep properties of temperature and material. It is important to enhance the resist rut ability and high temperature creep properties of the asphalt concrete in high temperature, and should pay attention to the early compaction of asphalt concrete pavement and the formation of the stone-to-stone structure ; the growth of rutting will slow along with the increasing of traffic ; the elastic parameters of the asphalt concrete pavement can almost be negligible. The calculation results of different pavement structures show that, the pavement structure has great influence on the rutting of asphalt concrete pavement. The main source of permanent deformation comes from the top layer and the intermediate layer. It is im- portant to select surface materials with excellent high temperature creep performance to decrease the rutting, especially the selection of top layer material.