沥青混合料中超声波传播规律研究

Study on Ultrasonic Propagation Rule in Asphalt Mixture

利用非金属超声波检测仪,对沥青混凝土AC-13、沥青碎石AM-13以及排水型沥青混合料OGFC-16三种车辙板进行波速Vs的测定,并考虑探头布置方式、耦合剂、仪器参数等外在因素对Vs的影响。结果表明,探头布置方式以及耦合剂对Vs有较大影响;而仪器参数对Vs的影响较小。Vs随着空隙率VV的增加而减小,随着密度ρ、动弹性模量E的增加而增大,且有较明显的线相关性。而沥青混合料的Vs与强度之间不具有明显相关性。此外,通过UTM试验机以及Vs计算所获得的E具有较大差异,可通过校正因子建立二者间的关系。

Using the advanced non-metallic ultrasonic detector, the wave velocity Vs was measured on three ruts of asphalt concrete AC-13, asphalt gravel AM-13 and OGFC-16, and the influence of external factors such as probe arrangement, coupling agent and instrument parameters on Vs was considered. The results show that the probe arrangement and coupling agent have great influence on Vs. The influence of instrument parameters on Vs is limited. Vs decreased with the increase of void fraction VV, and increased with the increase of density and dynamic elastic modulus E, both of which had obvious linear correlation. However,there was no significant correlation between Vs and strength of asphalt mixture. In addition, the E obtained by UTM testing machine and Vs calculation are quite different, and the relationship between the two types of E can be established by the correction factor.