形状记忆合金智能沥青路面的变形特性研究

Deformation Characteristics of Smart Asphalt Pavement Embedded with Shape Memory Alloy Wires

利用形状记忆合金的形状记忆效应,制备具有自修复功能的沥青混合料。采用热分析、力学测试仪对形状记忆合金丝材的相变行为与形状恢复性能进行表征,用车辙变形恢复试验验证沥青混合料的自修复性能。结果表明形状记忆合金丝材显示出B2-R-B19’两步马氏体相变,记忆合金丝材在预拉伸应变为10%时显示出约7.8%的可恢复应变。将形状记忆合金丝材与沥青混合料复合能够显著提高车辙试样的变形恢复率,沥青混合料的形状恢复率还受形状记忆合金丝材的铺设方式影响,其中铺设双层相互垂直形状记忆合金丝材的车辙试样平均变形恢复率高于铺设单层形状记忆合金丝材的车辙试样变形恢复率。

The asphalt mixtures with self-repairing function were developed by utilizing shape memory effect of shape memory alloys. The phase transformation behavior and shape recovery properties of the shape memory alloy wires were characterized by differential scanning calorimeter（DSC） and mechanical tester. The deformation recovery experiments were carried out on wheel track samples to verify the self-healing performance of the bitumen pavement material. The research results show that the shape memory alloy wires presents two-stage B2-RB19 martensitic transformation and a recovered strain of 7.8% with 10% pre-strain. These shape memory alloy wires can improve the shape recovery rates of the wheel tracking samples significantly. The paving mode of the shape memory alloy wires also plays an important role in the shape recovery rate of the asphalt mixtures. Finally,the wheel tracking samples paved with bidirection and double-layer shape memory alloy wires show higher shape recovery rate than that of samples paved with one-direction and one layer shape memory alloy wires.