弥合差距:评估实验室样品和混凝土结构的材料性能
Juan M Lozano-Valcarcel1, David Ov2, Thomas Kränkel1
1Chair of Materials Science and Testing, Centre for Building Materials, School of Engineering and Design, Technical University of Munich, 80333 Munich, Germany.
Materials (Basel, Switzerland)
|June 28, 2023
概括
混凝土结构面临着由于化物和碳化物进入的铁杆腐蚀风险. 现场试样显示材料的抗性低于实验室测试,特别是固化不足,影响耐用性.
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
- 腐蚀科学 腐蚀科学
背景情况:
- 在混凝土中,钢铁铁杆腐蚀是一个主要的结构性问题,由化物入侵和碳化驱动.
- 现有的模型模拟腐蚀的启动,但往往依赖于实验室衍生的材料特性.
- 实验室材料的电阻与实体结构的电阻之间存在差异,表明性能差距.
研究的目的:
- 在实验室和现场固化条件下比较混凝土样本的材料耐力.
- 评估不同固化时间对混凝土抗腐蚀因素性能的影响.
- 调查混凝土构成和固化对抗化物和碳化物的影响.
主要方法:
- 一项涉及实验室样本和现场测试墙壁/五个建筑工地板块的比较研究.
- 实验室样品的标准欧洲固化与外固化 (7天) 和田间样品的有限表面固化 (1天) 相比.
- 测试压力强度,弹性模量,化物进入阻力和碳化率.
主要成果:
- 实地试样始终表现出比实验室试样更低的材料阻力 (压力强度,弹性模量,入,碳化).
- 较短的固化时间,特别是表面固化的一天,显著降低了性能.
- 不充分的固化加剧了对化物耐药性和碳化深度的负面影响.
结论:
- 实验室产生的材料特性可能会高估混凝土结构的现实性能.
- 固化条件显著影响混凝土的耐用性和耐腐蚀剂的耐受性.
- 接受标准应考虑交付的混凝土质量和实际的现场结构性能.
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