Concrete weight coating: Mitigation of alkali-silica reaction and sulfate attack

混凝土重量涂层：减轻碱硅反应和硫酸盐侵蚀

基本信息

批准号：
484184-2015
负责人：
Hooton, Douglas
金额：
$ 1.82万
依托单位：
University of Toronto
依托单位国家：
加拿大
项目类别：
Engage Grants Program
财政年份：
2015
资助国家：
加拿大
起止时间：
2015-01-01 至 2016-12-31
项目状态：
已结题

来源：
https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=584162
关键词：
Concrete weight coating Mitigation alkali

项目摘要

Undersea oil and gas pipelines typically are coated with high density concrete to counteract buoyancy. These coatings must be durable over the life of the pipeline in an aggressive seawater environment. As these coatings are often applied in various locations around the world and involve fairly large volumes of concrete, local materials must be used. The aggregates and cementitious materials must be tested for their durability when used together in concrete pipe coatings. Alkali-silica reaction and both internal & external sulfate attack are well known causes of deterioration in normal concrete but not much is known or studied as to the impacts of these chemical reactions on the deterioration and expansion of dry mix concrete used by ShawCor for its concrete coatings. In this project, ShawCor will provide both raw materials from specific locations and cast simulated pipe coatings into test specimens. The aggregate materials have already been tested by some standard test methods, but the University of Toronto will evaluate them by new, non-standard rapid methods, that may be of use to Shawcor in future investigations. In addition, the resistance of the simulated dry-cast pipe coatings will be investigated for their resistance to both alkali-silica reaction and both internal & external sulfate attack. The results of this research will help ShawCor determine the appropriateness of their existing materials specifications and in the development of new specifications.

海底石油和天然气管道通常涂有高密度混凝土以抵消浮力。这些涂层必须在腐蚀性海水环境中的管道使用寿命内保持耐用。由于这些涂料经常应用于世界各地，并且涉及相当大量的混凝土，因此必须使用当地材料。当骨料和水泥材料在混凝土管道涂层中一起使用时，必须测试其耐久性。碱硅反应以及内部和外部硫酸盐侵蚀是普通混凝土劣化的众所周知的原因，但对于这些化学反应对 ShawCor 用于其混凝土的干混混凝土的劣化和膨胀的影响了解或研究不多涂料。在该项目中，ShawCor 将提供来自特定地点的原材料并将模拟管道涂层铸造成测试样本。这些骨料已经通过一些标准测试方法进行了测试，但多伦多大学将通过新的非标准快速方法对其进行评估，这可能对Shawcor在未来的调查中有用。此外，还将研究模拟干铸管道涂层的耐碱-二氧化硅反应以及内部和外部硫酸盐侵蚀的能力。这项研究的结果将帮助 ShawCor 确定其现有材料规格和新规格开发的适当性。