透水沥青混凝土单轴冲击压缩特性研究

为研究透水沥青混凝土的动态力学特性,采用74 mm钢质分离式霍普金森压杆装置对不掺纤维和掺0.3%聚酯纤维的透水沥青混凝土进行了不同应变率的单轴冲击压缩试验。研究表明,透水沥青混凝土具有明显的应变率效应,试件压缩率随着应变率的增大而提高,掺聚酯纤维透水沥青混凝土的压缩率是不掺纤维的1.2倍左右;透水沥青混凝土的动态应力-应变曲线可分为弹性变形阶段、塑性变形阶段和破坏阶段。从试件的破坏形态可以看出,集料的断裂是透水沥青混凝土破坏的主要原因。在透水沥青混凝土中掺加聚酯纤维能够延缓裂缝的出现和开展,提高材料的冲击抗压强度,增幅最大为45.1%。

Uniaxial impact compressive characteristics of permeable asphalt concrete

In order to investigate the dynamic characteristics of permeable asphalt concrete, 74mm steel Split Hopkinson pressure bar apparatus has been used to conduct uniaxial impact compressive test in various strain rates for permeable asphalt concrete with polyester fiber content of 0 and 0.3%. The research shows that there is a significant strain rate effect in permeable asphalt concrete and the specimen compression ratio grows with strain rate increasing. The specimen compression ratio of permeable asphalt concrete with polyester fiber is about 1.2 times as large as that without polyester fiber. Dynamic stress-strain curve of permeable asphalt concrete includes 3 stages, elastic deformation stage, plastic deformation stage and failure stage. From the failure mode of permeable asphalt concrete, it can be seen that the aggregate fracture is the main reason for permeable asphalt concrete failure. Polyester fiber in permeable asphalt concrete can delay cracks appearing and spreading and improve dynamic compressive strength. The largest strength increasing amplification can reach 45.1%.