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.

混凝土结构越来越多地根据基于性能的规范建造。这导致了行业的创新，因为生产商能够以新的方式利用传统材料或非传统材料，因为它们不再受到规定要求的限制。拟议的计划将包括新兴水泥系统的耐久性研究，如石灰石水泥，新开发的混合水泥和碱激活系统。性能规范通常包括对现场生产的样品进行的标准化测试。不符合性能措施可以追溯到不适当的混合料交付，但也可能是由于不良的施工实践。由于后者没有得到很好的研究，计划检查目前的耐久性测试的检测（识别）不良固化或巩固混凝土的敏感性。随着大规模项目的建设进展迅速，需要及时确定合规性。由于它是重要的是测试实际现场浇筑混凝土的性能发展，发展原位无损检测是必要的。该计划将研究吸收，表面电阻率和嵌入式电传感器等方法在这种情况下的使用。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，因此也将对这些影响进行研究。该计划旨在通过研究材料选择和场地问题对耐久性的影响，结合联合收割机实验室和现场测试，对混凝土系统采取新的方法。原始的贡献，预计对耐久性差的安置做法的影响，提供有用的信息，生产商和承包商就现场问题，以及适当的早期原位测试。这项研究的结果有可能显着影响混凝土性能的现场测量方法，并提高工程师和行业的知识。