【作者】 连丽；

【导师】 水中和；

【作者基本信息】 武汉理工大学 ， 建筑材料与工程， 2006， 硕士

【摘要】 随着当代建筑技术的飞速发展,对混凝土材料的应用性能要求越来越高。用具有高强度、高耐久性、高工作性等特性的高性能混凝土代替传统的混凝土结构物和建造在严酷环境中的特殊结构,有着显著的经济效益。然而,混凝土材料的性能与微观结构有着直接的关系,如:孔结构、界面过渡区结构、配合比组成等。本文主要采用偏光显微镜图像分析系统和显微硬度仪两种测试分析手段研究混凝土的显微结构,试图探寻混凝土显微结构与性能的关系。基于此,本文主要做了以下几个方面的研究: 1.运用偏光显微镜图像分析法与压汞测孔法两种测试分析手段,研究了水灰比、矿物细掺料对高性能混凝土、普通混凝土、低强度混凝土的孔结构和混凝土强度的影响。 2.采用显微硬度仪研究了水灰比、矿物细掺料对混凝土界面过渡区结构的影响,并分析了其对混凝土抗压强度的影响。 3.利用偏光显微镜图像分析法对硬化混凝土的配合比进行了研究。 研究结果表明,偏光显微镜图像分析法与压汞法测得的孔隙率值大小不同,但发展趋势相近;孔隙率的大小对混凝土的抗压强度的影响随混凝土种类的不同而不同,对于高性能混凝土来说,孔隙率越大,强度就越低。随着水灰比的增大,影响混凝土强度的因素增多,孔隙率的影响程度逐渐下降。界面过渡区结合的好,混凝土的强度就高。水灰比对界面过渡区的影响非常大,随着水灰比的增大,界面过渡区结构显著变差。运用偏光显微镜图像分析法测定的已硬化混凝土中石料含量、砂料含量及水泥石的含量,在水灰比为0.3时,测量误差在5%之内,随着水灰比的增大,其测量误差也逐渐增大。 可见,只有混凝土材料的显微结构得到改善,才能设计出具有高性能的混凝土。而偏光显微镜图像分析系统是一个直观、简便、快捷、有效的检测混凝土显微结构的测试方法,且制样简单,费用低,具有显著的经济效益。更多还原

【Abstract】 With the rapid development of the construction technique, the demand for the applied properties of concrete materials have been raising accordingly. For high performance concrete’s desired properties include high strength, long durability and good workability, it has been shown remarkably economic in replacing traditional concrete structure and constructing special structure using in harsh environment. The performance of concrete materials relates directly to their microstructure, such as pore structure, interface structure and composition. This thesis mainly analyzes the microstructure of concrete with the application of the image analysis’s system with polarizing microscope and microhardness testing machine aiming to probe the relationship between the microstructure of concrete and its properties. Based on this, the research focuses on the following respects:1. To study the effects of ratio of water and cement and mineral additive on the pore structure and the strength of high performance concrete, ordinary concrete and low-strength concrete, with the application of the image analysis’s system with polarizing microscope and MIP( method of mercury intrusion pore measurement);2. To research the effects of ratio of water and cement、 mineral additive on the interface structure by using microhardness testing machine, and to analyze their effect on the resist compression strength of concrete;3. To probe the combination of hydrated concrete with the application of the image analysis’s system with polarizing microscope It can be concluded from the research data that: the porosity values by using the image analysis’s system with polarizing microscope and MIP differ from each other but their developmental trends are close;the effect of porosity on the resist compression strength of different kinds of concrete differs;as to high performance concrete, the higher the porosity, the lower the strength will be;as the effects of ratio of water and cement raises and the factors affecting the strength of concrete increase, the effect of porosity declines;the better the interface structure combines, the higher the strength will be;the ratio of water and cement is an essential factor for the interface—as the ratio of water and cement raises, the interface structure notably worsens;While measuring the contents of stones, sands and cement by the image analysis’s system with polarizing microscope, the measure error is within 5% when the ratio of water and cement is 0.3;as the ratio of water and cement raises, the error enlarges.In a word, only by improving the microstructure of concrete materials can high performance concrete be composed, the image analysis’s system withpolarizing microscope is a direct-viewing, convenient, efficient and effective method for testing the microstructure of concrete;what’s more, it is easy to make samples and low at expense, which is of remarkable profit.更多还原