由来自加拿大安大略省金斯顿的AAR反应性聚合物产生的和传播的损害
Cassandra Trottier1, Leandro F M Sanchez1
1Department of Civil Engineering, Faculty of Engineering, University of Ottawa, Ottawa, ON K1N 6N5, Canada.
Materials (Basel, Switzerland)
|January 11, 2024
概括
与-碳酸盐反应 (ASR) 相比,-碳酸盐反应 (ACR) 造成了明显的混凝土损伤. 显微镜显示,ACR主要是裂水泥糊,与ASR不同.
科学领域:
- 材料科学 材料科学 材料科学
- 土木工程 土木工程是指土木工程.
- 混凝土的耐用性 混凝土的耐用性
背景情况:
- 在混凝土中发生碳酸盐反应 (ACR) 损伤的确切原因尚不清楚.
- 扩张和裂纹,常见的应急特征,经常被错误地归因于-反应 (ASR).
- 区分ACR与ASR对于准确的混凝土评估和修复至关重要.
研究的目的:
- 为了评估由ACR敏感反应性聚合物引起的混凝土损伤.
- 使用各种测试方法,比较ACR和ASR的损伤机制.
- 区分ACR作为一个独特的具体救援机制.
主要方法:
- 使用了机械测试,特别是直接剪切测试.
- 使用显微镜,包括损伤评级指数 (DRI),来评估裂纹图案.
- 分析了具有不同诱导膨胀水平 (0-0.20%) 的混凝土样本.
主要成果:
- 显微镜分析 (DRI) 显示了ACR行为与ASR不一致,表明了一个独特的应急机制.
- 机械测试无法区分ACR和ASR损伤.
- 显微镜显示,水泥中的裂占ACR的总裂的40-50%,与ASR的总裂 (≤20%) 相比.
结论:
- 碳酸盐反应 (ACR) 被证实是一种独特的混凝土应急机制,与-反应 (ASR) 不同.
- 显微镜对于识别ACR的特定损伤模式至关重要,主要是水泥糊的破裂.
- 虽然机械测试显示了类似的结果,但显微镜证据清楚地区分了ACR和ASR.
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