轴负活性混凝土的张力化和裂纹行为
Hamdi Abdulrahman1, Rahimah Muhamad1, Ahmad Azim Shukri2
1Razak Faculty of Technology and Informatics, Universiti Teknologi Malaysia, Kuala Lumpur 54100, Malaysia.
Materials (Basel, Switzerland)
|June 10, 2023
概括
与普通波特兰水泥混凝土相比,活性混凝土表现出更好的柔性行为和更均的抗拉强度. 这种环保材料增强了张力硬化,特别是增加了封闭性,为可持续建筑提供了更好的裂纹控制.
科学领域:
- 土木工程 土木工程是指土木工程.
- 材料科学 材料科学 材料科学
- 可持续建筑 可持续建筑
背景情况:
- 使用飞灰和性激活剂的活性混凝土 (AA) 是普通波特兰水泥 (OPC) 的可持续替代品.
- 了解AA混凝土的紧张强化,裂间距和裂宽度对于其结构应用和可用性至关重要.
- 现有的研究往往侧重于压缩性质,不太重视在使用负载下拉伸行为和裂纹发展.
研究的目的:
- 为了评估活性混凝土的张力刚性和裂纹性能.
- 为了研究压力强度和混凝土盖面与杆面直径比对AA混凝土破裂行为的影响.
- 将AA混凝土与OPC混凝土的破裂性能进行比较,并评估现有的预测模型.
主要方法:
- 在环境条件下在180天内造和固化AA和OPC混凝土标本.
- 测试混凝土镜以评估轴向裂变力,裂变应变和张力强化因子 (β).
- 分析裂间距和宽度,并将实验结果与EC2和ACI 224R代码的预测进行比较.
主要成果:
- 与OPC混凝土的脆性失败相比,AA混凝土表现出更多的柔性行为和同时发生裂.
- 增加混凝土盖面与条形直径的比率,增加了压力硬化,并延迟了AA混凝土的裂纹形成.
- EC2代码低估了裂宽度,而ACI 224R提供了更好的预测AA混凝土的裂宽度.
结论:
- 与OPC混凝土相比,活性混凝土表现出优越的张力强化和柔性性能.
- 封闭在改善AA混凝土的裂纹行为和张力刚性方面发挥着重要作用.
- 需要精细的模型来准确预测活性混凝土结构中的裂间距和宽度.
相关概念视频
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