CAJ | 학술논문

对静力、动力拉伸荷载条件下混凝土的细观破损过程进行了CT 试验研究，获得了试样内部裂纹萌生、扩展、贯通的全过程CT图像。通过对CT 图像及图像兴趣区中整体统计区域、局部统计区域CT 数均值的分析，研究了混凝土拉伸荷载条件下细观破损过程。结果表明：静力拉伸荷载条件下，裂纹在界面的薄弱区域形成后逐渐往相邻的薄弱部位扩展，两个统计区域CT 数均值呈降低趋势，试样破坏时伴有少量骨料被拉断的现象；动力拉伸荷载条件下，裂纹从界面薄弱区域形成后追随最快的路径扩展，局部统计区域CT 数均值呈下降趋势，而整体统计区域CT 数均值变化幅度较小，破坏后骨料沿界面脱离砂浆粘结，且试样破裂面更为平整；由于加载速率的提高，骨料被拉断的现象非常显著。
대정력、동력랍신하재조건하혼응토적세관파손과정진행료CT 시험연구，획득료시양내부렬문맹생、확전、관통적전과정CT도상。통과대CT 도상급도상흥취구중정체통계구역、국부통계구역CT 수균치적분석，연구료혼응토랍신하재조건하세관파손과정。결과표명：정력랍신하재조건하，렬문재계면적박약구역형성후축점왕상린적박약부위확전，량개통계구역CT 수균치정강저추세，시양파배시반유소량골료피랍단적현상；동력랍신하재조건하，렬문종계면박약구역형성후추수최쾌적로경확전，국부통계구역CT 수균치정하강추세，이정체통계구역CT 수균치변화폭도교소，파배후골료연계면탈리사장점결，차시양파렬면경위평정；유우가재속솔적제고，골료피랍단적현상비상현저。
The real time scanning observation on meso damage process in concrete was carried out using CT technology .CT images of crack propagation ,coalescence and failure were obtained under static and dynamic tension .Meso‐damage mechanism of concrete under tension was analyzed the mean CT numbers in large statistical region small statistic region of scanning layers ROI .The results showed that the cracks developed in the interface of weak region and expanded to adjacent weak partsthe mean CT numbers of the two statistical regions showed decreasing trend . Parts of aggregates were ruptured when the concrete was damaged under static tension .While in small statistic region ,the cracks developed in the interface of weak region and expanded along the fastest path ,and the mean CT numbers showed a decreasing trend The mean CT numbers in large statistical region changed slightly . The aggregate divorced from mortar along interface ,and the failure plane was smoother when the concrete was damaged under dynamic tension .So , the aggregate was ruptured obviously because the loading rate was higher .