在单轴压缩下,具有不同的固化年龄和岩石填充比率的模型岩石填充混凝土的力电特性
Cheng Hua1, Xiaochun Lu1, Tao Luo2
1College of Hydraulic and Environmental Engineering, China Three Gorges University, Yichang 443000, China.
The Science of the total environment
|August 14, 2024
概括
分析岩石填充混凝土的力电特性揭示了变形和故障的前体信息. 电阻力和压力强度随着年龄和岩石填充比率的增加而非线性增加,而孔隙性则减少.
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.
- 地质技术工程 地质技术工程
背景情况:
- 充满岩石的混凝土是一种至关重要的建筑材料,但了解其早期的机械行为和压力下故障机制对于结构完整性至关重要.
- 电力特性,特别是电阻,提供了一种非破坏性的方法来监测内部状态并预测混凝土结构的性能.
- 早期年龄评估对于确保岩石填充混凝土结构的长期可靠性和安全性至关重要.
研究的目的:
- 在单轴压缩下研究岩石填充混凝土的力电特性.
- 分析岩石填充比率和固化年龄对电阻力和孔隙结构的影响.
- 建立用于预测电阻和损害演变的数学模型.
主要方法:
- 准备了四种不同的岩石填充比率的模型岩石填充混凝土变化.
- 采用双电极交流电试验方法,测量在单轴压缩下电阻.
- 低场核磁共振技术被用来检查各种固化年龄 (1,3,7,14,28天) 的微观孔隙结构.
主要成果:
- 压力强度和电阻率表现出与固化年龄和岩石填充比率的非线性增加.
- 孔隙性显示出非线性下降,表明随着时间的推移和岩石含量增加,内部孔隙结构的细化.
- 在单轴压缩下,电阻遵循一个四个阶段的模式 (快速下降,缓慢下降,稳定,缓慢增加),与裂的发展相关联.
结论:
- 电阻力作为岩石填充混凝土中变形和故障前体的可靠指标.
- 数学模型成功地被开发出来,可以根据岩石填充率和固化年龄来预测电阻和损伤.
- 这些发现可以更好地预测损坏程度,并提高早期岩石填充混凝土结构的可靠性.
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