粗骨料对沥青混凝土开裂阻力影响分析

沥青混凝土是典型的非均匀材料,在进行力学分析时通常是将其视为均匀、各向同性体,但是理论分析结果很难与实际相符合。同时均质化假设也很难解释含大粒径骨料的沥青碎石作为防裂层的抗裂性能优于小粒径沥青混凝土的现象。笔者通过在均质的沥青混凝土引入一个粗骨料,应用断裂力学平面有限元程序系统地分析了粗骨料对沥青混凝土抗裂性能的影响,分析结果可以较好地解释大粒径沥青混凝土的抗裂性能优于小粒径沥青混凝土的机理。因此,使用大粒径骨料沥青混泥土能够改善路面的使用寿命。

THE EFFECT OF COARSE AGGREGATE ON CRACKING RESISTANCE OF ASPHALT CONCRETE

Asphalt concrete is a typical non-homogeneous material, but it is usually treated as a homogeneous and isotropic body in mechanical analysis. This causes the results of theoretical analysis hardly in agreement with actual. Meanwhile, it can hardly interpret the phenomena that the crack resistance of asphalt concrete containing large stone aggregate is larger than that of containing little stone aggregate. The authors use coarse aggregate in homogeneous asphalt concrete and analyze the effects of coarse aggregate on cracking resistant of asphalt concrete by using a fracture mechanistic finite element method. The results can interpret the mechanism why the crack resistance of asphalt concrete containing large stone aggregate is larger than that of containing little stone aggregate. Therefore, large stone aggregate asphalt concrete can improve pavement use life-span.