在酸腐蚀后,混凝土石灰岩复合物的损伤构成模型和机械性能
Jie Wang1, Bin Du1, Mingxuan Shen2
1College of Civil Engineering, Guizhou University, Huaxi District, Guiyang, 550025, Guizhou, China.
Scientific reports
|January 13, 2025
概括
酸性腐蚀显著降解混凝土 - 石灰石复合材料 (CLC),降低强度和弹性模量. 一个新的模型准确地预测了CLC在酸性条件下的机械行为,这对岩地区的基础设施至关重要.
科学领域:
- 地质技术工程 地质技术工程
- 材料科学 材料科学 材料科学
- 环境科学 环境科学
背景情况:
- 由于长期的酸性侵蚀,卡斯特地区面临基础设施退化.
- 酸性条件损害了工程结构的物理和机械性能.
研究的目的:
- 在酸性腐蚀下研究混凝土 - 石灰石复合材料 (CLC) 机械性能降解模式.
- 分析影响CLC的腐蚀机制.
- 在酸性环境中开发CLC行为预测模型.
主要方法:
- 已制造的CLC样本暴露在不同pH值 (7,5和3) 的酸性溶液中.
- 进行三轴压缩试验以分析机械性能.
- 应用了Lemaitre的应变等价假说和微元素强度的韦布尔分布来模型损伤.
主要成果:
- 随着pH值的下降,酸性腐蚀显著降低了CLC的峰值强度和弹性模量.
- 峰值强度下降了16.6% (pH 5) 和11.92% (pH 3).
- 弹性模块下降了25.36% (pH 5) 和23.13% (pH 3).
- 限制压力大大提高了峰值和残余强度,残余强度从8.2 MPa增加到86.93 MPa (0-10 MPa).
结论:
- 酸性腐蚀严重影响CLC的机械性能和故障模式.
- 一个经过验证的损害构成模型准确地模拟了在酸性攻击下CLC应力-应变曲线.
- 该模型为预测酸性环境中的石灰岩混凝土结构性能提供了基础.
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