Innovative and sustainable shrinkage-compensating concretes

创新且可持续的补偿收缩混凝土

• 批准号: RGPIN-2017-06916
• 负责人: Bissonnette, Benoît
• 金额: $ 2.04万
• 依托单位: Université Laval
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=712498
• 关键词: Innovative; sustainable; shrinkage; compensating; concretes

This project is part of a continuing effort at CRIB Laval (Laval University) intended to help establishing concrete repair as a legitimate engineering discipline. Ultimately, the fundamental objective is to provide the repair industry with the knowledge required to implement rational design methods and specifications for repairs. In that quest, the achievement of dimensional compatibility remains one of the most important considerations in order to consistently achieve lasting repair works that do not undergo harmful cracking. Drying shrinkage of Portland cement concrete is generally inevitable and, although its magnitude can be reduced by optimizing or modifying the composition parameters, it remains significantly larger than its ultimate tensile strain. Conversely, the use of shrinkage-compensating concrete (ShCC) may allow to achieve a zero-dimensional balance with respect to drying shrinkage, through the use of a mineral expansive agent. The experimental work carried out in recent years at Laval University to evaluate the potential of shrinkage-compensating concretes (ShCC) for use as repair materials has in fact yielded quite promising results. Nevertheless, more research is required to turn ShCC systems into a truly dependable and versatile repair option. Among the issues still unresolved, the engineering behind the shrinkage compensation process for repairs has yet to be developed. The overall influence of the type of expansive processes and their effectiveness with a variety of cement/binder systems needs to be investigated in depth. The anticipated research work will provide a basis for optimizing specifications, detailing and construction methods (repair thickness, bonding or anchoring, material selection, curing technique and duration, etc.) of ShCC repairs. Another aspect that needs to be addressed is the lack of suitable tests methods to characterize ShCC, to guide the specifications and to perform quality control. Efforts will be devoted to adapt or develop test procedures intended to better capture the particular volume change behavior of ShCC's. While the research program will be primarily dedicated to the development of more durable and sustainable shrinkage-compensating repair concretes, an objective of the research is to evaluate whether shrinkage compensation can be successfully exploited in some other specialty concretes. Ultimately, the findings are expected to benefit the overall concrete construction industry towards sustainability.

该项目是CRIB Laval（拉瓦尔大学）持续努力的一部分，旨在帮助将混凝土修复建立为一门合法的工程学科。最终，基本目标是为维修行业提供实施合理设计方法和维修规范所需的知识。在这一过程中，实现尺寸兼容性仍然是最重要的考虑因素之一，以便始终实现持久的修复工作，而不会发生有害的开裂。波特兰水泥混凝土的干缩通常是不可避免的，尽管其大小可以通过优化或修改组成参数来减小，但它仍然明显大于其极限拉伸应变。相反，通过使用矿物膨胀剂，使用收缩补偿混凝土（ShCC）可以使干燥收缩达到零维平衡。近年来在拉瓦尔大学进行的实验工作，以评估收缩补偿混凝土（ShCC）作为修复材料的潜力，实际上产生了相当有希望的结果。然而，需要更多的研究来将ShCC系统变成一个真正可靠和通用的维修选择。在尚未解决的问题中，修复收缩补偿程序背后的工程尚未开发。需要深入研究膨胀过程类型的总体影响及其对各种水泥/粘合剂体系的有效性。预期的研究工作将为优化ShCC修复的规格、细节和施工方法（修复厚度、粘接或锚固、材料选择、养护技术和工期等）提供依据。需要解决的另一个方面是缺乏适当的测试方法来表征ShCC、指导规范和执行质量控制。将致力于调整或开发旨在更好地捕捉ShCC的特定体积变化行为的测试程序。虽然研究计划将主要致力于开发更耐用和可持续的收缩补偿修复混凝土，但研究的一个目标是评估收缩补偿是否可以成功地应用于其他一些特种混凝土。最终，研究结果预计将有利于整个混凝土建筑行业的可持续发展。