摘要
微波加热是沥青混凝土路面的一种新型绿色养护技术,但目前微波吸收效率低下与沥青混凝土导热能力差是阻碍其推广应用的关键。基于阻抗匹配理论,考虑到掺加单一微波增强剂的局限性,提出一种改进的二元电磁复合型微波增强剂;将SiC和Fe_(3)O_(4)二元复合作为微波增强剂,采用矢量网络分析仪对微波增强剂样品的电磁参数进行测量。考虑到实验室缺少测量沥青混凝土内部温度的有效方法,采用COMSOL Multiphysics软件对微波加热沥青混凝土的温升速率和热量分布进行数值模拟,同时对其路用性能进行试验研究。研究结果表明:当SiC和Fe_(3)O_(4)的质量比是1∶2时(S_(1)F_(2)),S_(1)F_(2)的反射损耗达到了-22.12dB,比纯SiC的反射损耗低13.97dB。掺S_(1)F_(2)的沥青混凝土的平均升温速率为0.322℃/s,是对照组的1.87倍,并且高于单掺SiC(0.212℃/s)和Fe_(3)O_(4)(0.231℃/s)的沥青混凝土,且热量分布最均匀;相较于单相微波增强剂,掺二元复合材料的沥青混凝土微波吸收能力更强;同时,掺S_(1)F_(2)的沥青混凝土的抗水损害性能有一定程度的提高。
It is important for improving the microwave absorption capacity of asphalt concrete in order to promote the application of microwave heating in pavement maintenance.Based on the impedance matching theory,SiC-Fe_(3)O_(4) binary composites were prepared and the network analyzer was used to measure the electromagnetic parameters of SiC-Fe_(3)O_(4).Considering that it is difficult to measure the internal temperature of asphalt concrete using experimental methods,the heating rate and heat distribution of asphalt concrete was simulated by COMSOL Multiphysics.Finally,the pavement performance of asphalt concrete containing SiC-Fe_(3)O_(4) was tested.The results show that when the mass ratio of SiC to Fe_(3)O_(4) is 1∶2(S_(1)F_(2)),the reflection loss of S_(1)F_(2) reaches-22.12 dB,which is 13.97 dB lower than that of SiC.The heating rate of the asphalt concrete containing S_(1)F_(2) is calculated as 0.322℃/s,which is 1.87 times that of control samples,and it is also higher than that of asphalt concrete containing either SiC(0.212℃/s)or Fe_(3)O_(4)(0.231℃/s).Meanwhile,the asphalt concrete containing S1F2 has the most uniform heat distribution.It can be concluded that the asphalt concrete containing the binary composite of SiC-Fe_(3)O_(4) has excellent microwave absorption ability.At last,the results of Marshall immersion test showed that asphalt concrete containing S_(1)F_(2) has better water resistance.
作者
刘小明
魏子奇
赵昱
Liu Xiaoming;Wei Ziqi;Zhao Yu(Central South University,Changsha 410075,China)
出处
《土木工程学报》
EI
CSCD
北大核心
2021年第12期116-123,共8页
China Civil Engineering Journal
基金
国家自然科学基金(52078499)。
