基于图像处理技术的混凝土碳化深度测量

Carbonation depth measurement based on digital image processing technique

针对现有混凝土碳化深度测量方法(直尺测量法)的不足,提出了一种新的测量方法.首先比较了照相机和普通扫描仪的不同工作原理和图像获取效果,介绍了利用专用扫描设备获取混凝土试件碳化图像的具体方法;对比RGB与HSV模式图像各通道的灰度直方图,给出了利用色相灰度图测量碳化深度的思路;并基于Matlab软件开发了相应的GUI程序,方便地实现了对图像的读入、裁剪、旋转、灰度处理、碳化深度测量及数据导出.为验证新方法的可靠性,分别采用常规测量与色相灰度图测量方法对多个试件的碳化深度进行测量并比较.结果表明,新方法不仅测量值准确,能有效减小人为误差、提高精度,而且在操作上具有明显的便利性并可大大减少试验工作量.因此,该种基于专用扫描设备获取混凝土试件碳化图像结合色相灰度图测量碳化深度的新方法,可以用于混凝土碳化深度测量,并且操作方便、测量结果可靠.

In view of the deficiencies in the existing measurement of carbonation depth of concrete, a new measuring method is presented here. The method of image acquisition （image of carbonized specimen） by using improved scanner is introduced and a new idea of using the hue gray scale image to measure the carbonation depth through comparison of every channel histogram of RGB and HSV is proposed. After that, a computer program GUI based on Matlab is developed to crop, rotate, gray and calculate the carbonation depth of concrete and exporting data conveniently. In order to verify the reliability of this new method, the carbonation depth of specimens is measured by two kinds of methods such as a conventional measuring method as well as a colour gray scale image processing method. The measured results show that the new method based on the special scanning apparatus is not only accurate for reducing human error greatly, but also convenient in operation for reducing the workload greatly.