基于破损演化理论的混凝土CT图像定量分析

QUANTITATIVE ANALYSIS OF CONCRETE CT IMAGES BASED ON DAMAGE-FRACTURE EVOLUTION THEORY

通过对混凝土CT图像影像特征的分析可以研究混凝土内部细观结构及裂纹变化的特点,但当前国内对混凝土的CT试验研究很少。将破损演化理论应用于混凝土CT图像的定量分析,利用完整度和破损度的变化分析试样各点的强度变化,解决了CT数分布范围广、不利于定量分析的问题;利用λ–水平完整域和λ–水平破损域实现从细观到宏观分析的过渡;进一步利用λ1–λ2截理的概念从CT图像中分别提取出裂纹区域、骨料区域、砂浆区域以及空气区域。提出量测各区域大小的方法,实现对混凝土各物相的分区描述,并在此基础上探讨破损演化理论在混凝土CT试验研究中的应用前景。

The characters of microstructure and crack change in concrete can be investigated by CT images.But now there is rare quantitative analysis of concrete CT images in China. Damage-fracture evolution theory has been applied to the quantitative analysis of concrete CT images. In such a way, the degrees of perfection and damage are used to analyze the strength of each variation, which solves the question that the distribution range of CT numbers is too wide. The transition from microscopic analysis to macroscopic one is accomplished on the basis of λ-level perfect field and λ-level damage-fracture field. Furthermore, the areas of cracks, aggregates, mortar and air are extracted from CT images according to λ 1-λ2 level intercepted section, Then, the approach to measure the size of each area has been put forward, which has realized the description of each substantial distribution. Based on this method, the application prospect of damage-fracture evolution theory to the experimental study on concrete CT image is discussed.