混凝土耐久性无损检测技术应用研究
发布时间：2019-05-10 04:23
【摘要】：随着我国城市化进程和基础建设的加快，混凝土耐久性问题也越来越得到人们的重视。本文依托于国家科技支撑计划项目-跨海集群工程混凝土结构120年使用寿命保障关键技术，研究了无损检测技术在混凝土耐久性质量控制方面的应用。根据FICK第二定律可知，氯离子扩散系数与钢筋保护层厚度对混凝土结构使用年限有着非常重要的影响。因此，本文重点研究了利用WENNER、探地雷达等无损检测技术方法对混凝土耐久性质量进行控制的应用，具体研究成果如下 1、通过开展现场试验、足尺模型与室内试验，建立WENNER法与RCM法两种试验方法所测得的混凝土电阻率与混凝土氯离子扩散系数的相关性。试验表明，足尺模型试验测得电阻率随龄期变化规律更加符合实体构件的电阻率随龄期变化规律，，混凝土电阻率ρ与混凝土氯离子扩散系数D的关系式为D=128.486。通过试验建立了实体构件混凝土电阻率ρ与氯离子扩散系数D的关系式D=128.4861.02ρ3.05，解决了现场构件无法进行破损性的氯离子扩散系数检测这一问题，实现了现场简单快速的控制混凝土耐久性质量的目标。 2、通过开展港珠澳大桥沉管隧道足尺模型试验确定了探地雷达测混凝土保护层厚度的偏差修正值为0.87mm。使用探地雷达对港珠澳大桥沉管隧道预制构件的10个管节共计64个节段的5600多根钢筋位置的混凝土保护层厚度进行了检测，分析总结了沉管隧道预制构件墙外侧、墙内侧、底板外侧的保护层厚度的偏差分布，达到了精准控制混凝土耐久性质量的要求。 3、对比分析了沉管隧道预制构件墙外侧、墙内侧、底板外侧保护层厚度偏差分布的差异。沉管隧道预制构件底板外侧保护层厚度偏差比墙外侧、墙内侧的偏差都小，因此要加强沉管隧道预制构件墙外侧、墙内侧绑扎钢筋、模板支护时的质量监测。
[Abstract]:With the acceleration of urbanization and infrastructure in China, the durability of concrete has been paid more and more attention. Based on the key technology of 120 years service life guarantee of concrete structure in cross-sea cluster project, the application of nondestructive testing technology in durability quality control of concrete is studied in this paper. According to FICK's second law, the chloride diffusion coefficient and the thickness of steel bar cover have a very important influence on the service life of concrete structures. Therefore, this paper focuses on the application of WENNER, ground penetrating radar and other nondestructive testing techniques to control the durability quality of concrete. The specific research results are as follows: 1. Through field test, full-scale model and laboratory test, The correlation between the concrete resistivity measured by the WENNER method and the RCM method and the chloride diffusion coefficient of the concrete is established. The test results show that the variation of resistance with age is more in accordance with the law of resistance of solid members with age, and the relationship between resistance of concrete and chloride diffusion coefficient D of concrete is D 鈮
本文编号：2473336
[Abstract]:With the acceleration of urbanization and infrastructure in China, the durability of concrete has been paid more and more attention. Based on the key technology of 120 years service life guarantee of concrete structure in cross-sea cluster project, the application of nondestructive testing technology in durability quality control of concrete is studied in this paper. According to FICK's second law, the chloride diffusion coefficient and the thickness of steel bar cover have a very important influence on the service life of concrete structures. Therefore, this paper focuses on the application of WENNER, ground penetrating radar and other nondestructive testing techniques to control the durability quality of concrete. The specific research results are as follows: 1. Through field test, full-scale model and laboratory test, The correlation between the concrete resistivity measured by the WENNER method and the RCM method and the chloride diffusion coefficient of the concrete is established. The test results show that the variation of resistance with age is more in accordance with the law of resistance of solid members with age, and the relationship between resistance of concrete and chloride diffusion coefficient D of concrete is D 鈮
本文编号：2473336
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