Improved durability testing for field placed concrete and emerging cement systems

改进现场浇筑混凝土和新兴水泥系统的耐久性测试

• 批准号: 312213-2013
• 负责人: Nokken, Michelle
• 金额: $ 1.75万
• 依托单位: Concordia University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=636063
• 关键词: Improved; durability; testing; field; placed

Increasingly, concrete structures are built according to performance-based specifications. This leads to innovation in the industry as producers are able to utilize traditional materials in new ways or unconventional materials since they are no longer constrained by prescriptive requirements. The proposed program will include durability investigations of emerging cement systems; such as limestone cements, newly developed blended cements, and alkali-activated systems. Performance specifications typically consist of standardized tests performed on site-produced specimens. Non-conformance to performance measures can be traced to improper mixture delivery, but could also result from poor construction practice. As the latter is not well studied, it is planned to examine the sensitivity of current durability tests for the detection (identification) of poorly cured or consolidated concrete. As construction proceeds rapidly on large scale projects, timely determination of compliance is desired. As it is important to test actual field-placed concrete as its properties develop, developments for in situ non-destructive testing are necessary. This program will examine such methods as absorption, surface resistivity, and embedded electrical sensors for their use in such instances. As changing site conditions, such as temperature and relative humidity may affect test results, these influences will be investigated as well. The program aims to take a novel approach to concrete systems through study of the impact of material selection and site issues on durability that will combine laboratory and field testing. Original contributions are anticipated regarding the influence of poor placement practices on durability providing useful information to producers and contractors regarding site issues as well as appropriate early situ testing. The results of this research have the potential to significantly influence the method in which concrete performance is measured on site and enhance the knowledge of engineers and industry.

越来越多的混凝土结构是根据基于绩效的规范构建的。这导致行业的创新，因为生产商能够以新的方式或非常规材料利用传统材料，因为它们不再受规定要求的约束。拟议的计划将包括对新兴水泥系统的耐用性调查；例如石灰石水泥，新开发的混合水泥和碱激活的系统。性能规格通常包括对现场生产标本进行的标准化测试。不符合性能指标的符合性可以追溯到混合物交付不当，但也可能是由于建筑习惯不佳而造成的。由于后者没有很好地研究，因此计划检查当前耐用性测试对固化效果不佳或固结混凝土检测（鉴定）的灵敏度。随着施工在大规模项目上的迅速进行，需要及时确定合规性。由于随着其特性的发展，测试实际场所的混凝土很重要，因此必须进行原位非破坏性测试的发展。该程序将检查吸收，表面电阻率和嵌入式电传感器等方法，以便在这种情况下使用。由于温度和相对湿度等现场条件的变化可能会影响测试结果，因此也将研究这些影响。该计划旨在通过研究材料选择和现场问题对将结合实验室和现场测试的耐用性的影响来采用一种新颖的方法来进行混凝土系统。预计，对于不良位置实践对耐久性的影响，将为生产者和承包商提供有关现场问题以及适当的早期原位测试的影响。这项研究的结果有可能显着影响在现场测量具体性能并增强工程师和行业知识的方法。