在高温下,含有pozzolans的混凝土的压力强度比率
Ghasem Pachideh1, Majid Gholhaki2, Ahlam Aljenabi2
1Sharif University of Technology, Iran.
Heliyon
|April 2, 2024
概括
在水泥中添加焦石和石可以提高环境温度下混凝土的强度. 然而,高温 (300-700°C) 降低了拉伸强度和C-S-H峰值强度,而150°C显示了最高的压力强度.
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.
- 环境科学 环境科学
背景情况:
- 由于高能耗和排放,水泥生产是污染的重要来源.
- 高温可能会对混凝土基础设施产生负面影响,在这种条件下需要进行性能研究.
研究的目的:
- 为了研究混凝土加热后的性能,使用青石和青石添加剂.
- 为了评估高温 (28°C至700°C) 对含有6%和10%的焦岩和岩的混凝土样本的影响.
主要方法:
- 准备的混凝土样本中含有不同百分比的石和石.
- 标本暴露在28°C,150°C,300°C和700°C的温度下.
- 使用XRD分析了压力强度,抗拉强度,C-S-H峰强度和波特兰含量.
主要成果:
- 在环境条件下,在90天内用6%和10%的焦石和石取代水泥增加了压力强度.
- 混凝土用10%的本托尼特加热到150°C显示压力强度增加了40%.
- 拉伸强度在300°C和700°C下降,对于具有pozzolans的标本.
- 在700°C时,C-S-H峰值强度显著下降,但在300°C时仍然相似.
- 在150°C加热的样本表现出最高的压力强度,而在700°C加热的样本表现出最低的压力强度.
结论:
- 石和石添加剂可以增强混凝土的环境压力强度.
- 虽然暴露在150°C可以提高压力强度,但较高的温度 (300°C-700°C) 会降低拉伸强度和C-S-H结构.
- 该研究提供了关于混凝土的热性能与基础设施弹性矿物添加剂的见解.
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