在暴露于高温后,活性砂混凝土的化物透性
Baomeng Zhou1,2,3, Qianmin Ma1,2,3, Rongxin Guo1,2,3
1Faculty of Civil Engineering and Mechanics, Kunming University of Science and Technology, Kunming 650500, China.
Materials (Basel, Switzerland)
|March 13, 2024
概括
高温增加了活性渣 (AAS) 混凝土中的化物透性. 诸如加热速度和冷却方法等因素对AAS混凝土有重大影响.
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.
- 建筑材料 建筑材料
背景情况:
- 全球火灾的增加需要评估结构材料在高温下的性能.
- 活性渣 (AAS) 混凝土显示出前景,但需要耐久性评估才能更广泛地应用.
- 化物透性是AAS混凝土暴露于热量的关键耐久性方面.
研究的目的:
- 为了研究AAS混凝土在高温暴露后的化物透性.
- 分析活性剂特性 (Na2O%,Ms) 对热损坏的AAS混凝土的影响.
- 为了确定各种加热模式 (速度,持续时间,冷却) 对AAS混凝土耐用性的影响.
主要方法:
- 暴露AAS混凝土标本在受控的高温下.
- 使用ASTM C1202充电通过方法评估化物透性.
- 活性剂度和模块的系统变化.
- 对加热速度,曝光时间和冷却方法进行受控的操纵.
主要成果:
- 随着温度的升高,AAS混凝土的化物透性会增加.
- 更快的加热,更长的高温持续时间和水冷却增加了孔隙性,降低了化物抵抗力.
- 由于孔隙溶液导电性,ASTM C1202方法的结果变得复杂,掩盖了激活器对透性的影响.
- 在AAS混凝土中较低的Na2O%和Ms可能与加热后较低的孔隙性和透度相关,需要进一步研究.
结论:
- 高温显著降低了AAS混凝土的化物耐受性.
- 加热模式,特别是快速加热,长时间暴露和水冷,会对AAS混凝土的耐用性产生负面影响.
- 需要进一步的研究来澄清激活剂特性对受热影响的AAS混凝土中化物透性的作用.
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