基于数字散斑相关法的紫外老化沥青混合料界面开裂特性

发布时间：2019-02-14 15:20

【摘要】：利用数字图像相关技术(DSCM)针对紫外光老化的沥青混合料(HMA)半圆试件弯拉试验中裂纹产生及扩展规律从细观角度进行表征,运用Vic-3D分析软件对沥青混合料半圆试件进行全场位移、应变计算,得到试件破坏过程的位移场、应变场。结果表明:通过对紫外光照的沥青胶浆、集料及界面水平方向应变场的对比分析,发现界面为沥青混合料最薄弱处,最易产生裂纹;进一步通过水平方向应变随载荷变化曲线的变化对HMA开裂时间进行分析,可以更好地将HMA微裂缝开裂时间与宏观裂缝开裂时间加以区分,且紫外老化后的HMA试样界面开裂时间明显缩短。同时,将相同的紫外老化前后的橡胶粉(CR)改性HMA试样与苯乙烯-丁二烯-苯乙烯(SBS)改性HMA试样的位移随载荷变化规律进行对比发现,经紫外老化后的CR改性HMA比紫外老化后SBS改性HMA具有更强的抗开裂能力及持荷能力。
[Abstract]:By using digital image correlation technique (DSCM), the crack generation and propagation law of (HMA) semi-circular specimens of asphalt mixture subjected to ultraviolet light aging was characterized from a meso point of view. The full-field displacement and strain of semi-circular asphalt mixture specimens were calculated by Vic-3D software, and the displacement field and strain field of the failure process were obtained. The results show that the interface is the weakest point of asphalt mixture and the most prone to crack through the comparison and analysis of the horizontal strain fields of UV irradiated asphalt mortar aggregate and interface. Furthermore, the crack time of HMA can be better distinguished from that of macroscopic crack by analyzing the change of horizontal strain with the change of load curve, so that the crack time of HMA microcrack can be better distinguished from that of macroscopic crack. The interfacial cracking time of HMA samples after UV aging was shortened obviously. At the same time, the displacement of HMA samples modified by rubber powder (CR) and styrene-butadiene-styrene modified HMA samples before and after UV aging were compared with those of HMA samples modified by styrene-butadiene-styrene. Compared with SBS modified HMA after UV aging, the CR modified HMA after UV aging has stronger cracking resistance and load holding capacity than that of SBS modified HMA after UV aging.
【作者单位】：内蒙古工业大学土木工程学院;
【基金】：国家自然科学基金(11462018) 内蒙古自然科学基金(2014MS0507)
【分类号】：U414

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