在水泥糊中添加的混合物西兰的评价
Bruna Aparecida Lamari1, Lidiane Fernanda Jochem1, Philippe Jean Paul Gleize2
1Academic Department of Civil Construction (DACOC), Technological Federal University of Paraná (UTFPR), Curitiba 81280-340, PR, Brazil.
Materials (Basel, Switzerland)
|November 27, 2024
概括
这项研究研究了silanes作为在水泥中的超级可塑剂的部分替代品. 虽然一些西兰酸盐降低了可加工性和强度,但甲基 propyltrimethoxysilane (MCPTMS) 显示出对关键性质产生最小影响的潜力.
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.
- 化学工程是化学工程的重要组成部分.
背景情况:
- 超级增塑剂对于提高水泥材料的可加工性至关重要.
- 锡兰正在被探索作为在水泥基层中的潜在添加剂.
- 为了开发先进的混凝土技术,了解silanes作为超级增塑剂的部分替代品的性能至关重要.
研究的目的:
- 评价三种不同的西兰 (VTES,AEAPTMS,MCPTMS) 在波特兰水泥糊中作为部分替代聚碳酸以为基础的超级增塑剂的性能.
- 评估不同水平 (20%和40%) 的西兰替代物对水泥糊的新鲜和硬化性能的影响.
- 为了分析用silanes修改的水化矩阵的水化动力学和机械性能.
主要方法:
- 制备水/水泥比率为0.186.6的水泥糊.
- 在20%和40%的水平上,用乙烯基三氧化 (VTES),n-(2-氨基乙烯) -3-氨基三氧化 (AEAPTMS) 和甲基基三氧化 (MCPTMS) 部分替代超级可塑剂.
- 评估新鲜性质:比重,被困空气,迷你沉降和异热热量计用于水化动力学.
- 硬化性质的评估:压力强度,屈曲强度,比重和7天和28天浸泡吸收.
主要成果:
- VTES和AEAPTMS显著降低了可加工性,并在两个替代水平上增加了空气含量.
- MCPTMS对可操作性和空气含量的影响最小.
- 与基准相比,所有修改了西兰的面粉都表现出延迟的水化动力学.
- 在所有西兰替代品中,屈曲强度都下降了.
- 压力强度下降,除了MCPTMS,它在7天和28天显示出可比或改善的强度.
- 所有样本都显示了高吸收率和空白指数值.
结论:
- 甲基基 propyltrimethoxysilane (MCPTMS) 显示出作为部分超可塑剂替代水泥糊的潜力,因为它对可加工性和保持压力强度的能力的负面影响有限.
- 乙烯基三氧化 (VTES) 和n-(2-氨基乙烯) -3-氨基三氧化 (AEAPTMS) 负面影响加工性和强度,限制了它们的适用性.
- 需要进一步的研究,以优化西兰的使用,并减轻对吸收和空气含量在水泥材料的负面影响.
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