在新鲜和硬化状态下对自压缩混凝土的超声波表征和机械性能
Mouhcine Benaicha1, Olivier Jalbaud2, Yves Burtschell2
1Structure and Materials Laboratory, National School of Architecture, Rabat, Morocco.
Ultrasonics
|April 8, 2025
概括
自压缩混凝土 (SCC) 中的超声速与粘度和屈服应力等质性质有很强的相关性. 这种先进的测试方法还可以准确地预测硬化混凝土.
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.
- 混凝土技术 混凝土技术
背景情况:
- 现有关于自压缩混凝土 (SCC) 的研究缺乏系统分析,将超声波参数与气质和机械性能相关联.
- 先进的超声波测试提供了对具体特征的非破坏性评估的潜力.
研究的目的:
- 系统地评估超声波参数与SCC的新鲜和硬化性能之间的关系.
- 确定超声速与关键的气质 (塑料粘度,屈服应力) 和机械 (压力强度,扬模) 性能之间的相关性.
主要方法:
- 利用先进的超声波测试技术来评估SCC的特性.
- 对参数进行了广泛的测试,包括空气含量,水吸收,塑料粘度,屈服应力,密度,压力强度和扬模.
- 分析了超声速与新鲜和硬化状态下的测量混凝土性能之间的相关性.
主要成果:
- 超声速显示出与塑料粘度 (R2=0.95),屈服应力 (R2=0.97) 和新鲜密度 (R2=0.99) 的强烈正相关性.
- 更高的超声速表明新鲜SCC的内部一致性,材料完整性,紧性和均性得到了增强.
- 在硬化的SCC中,超声速与压力强度 (R2=0.98-0.99) 和模量 (R2=0.96-0.98) 强烈相关.
结论:
- 超声速是SCC的质性质和新鲜状态特征的可靠指标.
- 超声波测试有效地预测了硬化SCC的机械性能和结构完整性.
- 这些发现支持优化SCC混合物设计,以提高建筑中的性能和耐用性.
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