[1] Guo Liping, Andrea Carpinteri, Sun Wei, et al. Measurement and analysis of defects in high-performance concretewith three-dimensional micro-computer tomography [J]. Journal of Southeast University (English Edition), 2009, 25 (1): 83-88. [doi:10.3969/j.issn.1003-7985.2009.01.018]

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Measurement and analysis of defects in high-performance concretewith three-dimensional micro-computer tomography()

基于三维微焦点CT图像对高性能混凝土内部缺陷的测量和分析

Journal of Southeast University (English Edition)[ISSN:1003-7985/CN:32-1325/N]

Volumn:

25

Issue:

2009 1

Page:

83-88

Research Field:

Materials Sciences and Engineering

Publishing date:

2009-03-30

Info

Title:

Measurement and analysis of defects in high-performance concretewith three-dimensional micro-computer tomography

基于三维微焦点CT图像对高性能混凝土内部缺陷的测量和分析

Author(s):

Guo Liping^{1, 2}, Andrea Carpinteri³, Sun Wei^{1, 2}, Qin Wenchao⁴

¹School of Materials Science and Engineering, Southeast University, Nanjing 211189, China
²Jiangsu Key Laboratory of Construction Materials, Southeast University, Nanjing 211189, China
³Department of Civil Engineering, University of Parma, Parma 43100, Italy
⁴YXLON International X-Ray GmbH Shanghai Rep.Office, Shanghai 200041, China

郭丽萍^{1, 2}, Andrea Carpinteri³, 孙伟^{1, 2}, 秦文超⁴

¹ 东南大学材料科学与工程学院, 南京 211189; ² 东南大学江苏省土木工程材料重点实验室, 南京 211189; ³ 帕尔马大学土木工程系, 意大利帕尔马 43100; ⁴ 德国依科视朗国际射线有限公司上海代表处, 上海 200041

Keywords:

high-performance concrete;  defect;  microstructure;  X-ray micro-focus computer tomography;  mineral admixtures

高性能混凝土;  缺陷;  微观结构;  X-射线微焦点CT;  矿物掺和料

PACS:

TU522.07

DOI:

10.3969/j.issn.1003-7985.2009.01.018

Abstract:

In order to investigate the effects of two mineral admixtures(i.e., fly ash and ground slag)on initial defects existing in concrete microstructures, a high-resolution X-ray micro-CT(micro-focus computer tomography)is employed to quantitatively analyze the initial defects in four series of high-performance concrete(HPC)specimens with additions of different mineral admixtures.The high-resolution 3D images of microstructures and filtered defects are reconstructed by micro-CT software.The size distribution and volume fractions of initial defects are analyzed based on 3D and 2D micro-CT images.The analysis results are verified by experimental results of water-suction tests.The results show that the additions of mineral admixtures in concrete as cementitious materials greatly change the geometrical properties of the microstructures and the spatial features of defects by physical-chemistry actions of these mineral admixtures.This is the major cause of the differences between the mechanical behaviors of HPC with and without mineral admixtures when the water-to-binder ratio and the size distribution of aggregates are constant.

为了揭示粉煤灰和磨细矿渣对混凝土微观结构初始缺陷的影响规律, 采用高分辨率X-射线微焦点CT(X-ray Micro-CT)图像对具有不同胶凝材料的4个系列高性能混凝土进行了研究.混凝土微观结构和缺陷过滤之后的高分辨率三维图像均由Micro-CT配套的图像软件进行了重建.基于二维和三维图像分析得到了混凝土内部缺陷的尺寸分布和体积分数, 并与常温饱水法的试验结果进行了对比.研究结果显示:矿物掺和料作为胶凝材料加入混凝土之后, 由于其颗粒填充效应和火山灰效应, 显著改变了硬化混凝土的微观结构特征以及初始缺陷的尺寸和空间分布特征;在水胶比和集料尺寸分布保持不变的条件下, 矿物掺和料的掺入与否, 是引起高性能混凝土展示出不同力学特性的主要原因.

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Memo

Memo:

Biographies: Guo Liping(1979—), female, doctor, lecturer, guoliping@seu.edu.cn;Sun Wei(1935—), female, doctor, professor, academician of China Engineering Academy, sunwei@seu.edu.cn.
Foundation items: The Scholarship Supported by Ministry of Education of China for Research Abroad(No.3037 [2006]), the Excellent Doctoral Dissertation Foundation of Southeast University(No.YBTJ-0512), the National Basic Research Program of China(973 Program)(No.2009CB623203).
Citation: Guo Liping, Andrea Carpinteri, Sun Wei, et al.Measurement and analysis of defects in high-performance concrete with three-dimensional micro-computer tomography[J].Journal of Southeast University(English Edition), 2009, 25(1):83-88.

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