Use of crystalline waterproofing technology and SCMs to develop sustainable and smart self-sealing materials

加拿大的基础设施需要既耐用又可持续的胶凝材料，用于新的和维修应用。该项目将专注于开发创新的水泥基材料，这些材料利用矿渣等工业废物，并与基于结晶防水技术的外加剂相结合。这些基于结晶技术的外加剂保持被动，直到水分进入混凝土的气孔，然后与这些水分反应，形成阻止气孔的晶体，使材料的渗透性降低。这一特性可以被用来开发智能材料，这种材料可以随着时间的推移而密封，因此被称为“自密封”。渗透性和“自封性”的降低提高了材料的耐久性，进而延长了使用这种材料的结构的寿命。晶态外加剂，如Kryton International Inc.生产的KIM已经使用了几十年，它在降低渗透率方面的有效性是众所周知的。然而，当这种外加剂与加拿大市场上最近推出的高掺量矿渣和波特兰石灰石水泥结合时，其相互作用尚不清楚。在这个项目中，将考虑一个由八种混合料组成的测试矩阵，变量包括炉渣含量、KIM的添加量和PLC的使用。将利用维多利亚大学的扫描电子显微镜和世界上最高倍率的扫描电子全息显微镜来研究不同混合料水泥相微观结构的变化。下一个里程碑将涉及表征各种混合物的受限塑料和干燥收缩开裂潜力。各种混合物的自密封特性将使用由申请人和行业合作伙伴共同发明的创新技术进行量化。该项目的最后阶段将包括测量长期模拟暴露后混凝土中的氯离子浓度。该项目的发现将有利于加拿大建筑业，也将使行业合作伙伴进一步了解KIM混合料，并导致智能自密封材料的开发。

Canadian infrastructure is in need of cementitious materials that are both durable and sustainable for use in new and repair applications. This project will focus on development of innovative cement-based materials that utilize industrial wastes like slag and are also combined with admixtures that are based on crystalline water proofing technology. These admixtures based on crystalline technology remain passive until moisture enters the pores of concrete and then react with this moisture forming pore blocking crystals making the material less permeable. This characteristic can be utilized to develop smart materials that can seal with time thus referred to as "self-sealing." The reduction in both permeability and "self-sealing" leads to improved durability of the material in turn extending the life of structures where this material is utilized. Crystalline based admixtures such as KIM (produced by Kryton International Inc.) have been used for decades and its effectiveness in reducing permeability is well understood. However, the interaction of this admixture when combined with high volume of slag and Portland Limestone Cement that was recently introduced in the Canadian markets is not known. In this project, a test matrix consisting of eight mixes with variables such as slag content, addition of KIM, and use of PLC will be considered. The change in the microstructure of the cement phase of the various mixes will be studied using Scanning Electron Microscope and world's highest magnification Scanning Transmission Electron Holography Microscope at the University of Victoria. The next milestone will involve characterizing the restrained plastic and drying shrinkage cracking potential of the various mixes. The self-sealing characteristics of the various mixes will be quantified using an innovative technique co-invented by the applicant and the industry partner. The final phase of this project will involve measuring the chloride ion concentrations in concrete after long-term simulated exposure. The findings of this project will be beneficial to the Canadian construction industry and will also allow the industry partner to further their understanding about KIM admixture and lead to development of smart self-sealing materials.