硫酸盐攻击对水泥处理聚合物的膨胀行为的影响
Qi Wang1, Jiankun Liu2,3, Pengcheng Wang4
1Research Institute of Highway Ministry of Transport, Beijing 100088, China.
Materials (Basel, Switzerland)
|April 9, 2024
概括
硫酸盐对水泥处理聚合物的攻击 (SACA) 导致基础设施的扩张. 硫酸盐含量是主要因素,0.5%是诱导扩张的最低值,影响道路和铁路的稳定性.
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
- 地质技术工程 地质技术工程
背景情况:
- 硫酸盐对水泥处理聚合物 (SACA) 的攻击导致道路基层和铁路基层的显著扩张和抬高.
- 了解影响SACA扩张的因素对于基础设施的耐用性和维护至关重要.
研究的目的:
- 研究各种因素对在硫酸盐攻击下SACA扩张行为的影响.
- 量化分析每个因素的敏感性,并确定扩张的主要原因.
- 为减轻SACA引发的扩张提供理论支持.
主要方法:
- 在60天内进行了实验室实验,以评估SACA扩张.
- 研究的关键因素包括硫酸含量,水泥含量,压缩程度,硫酸盐类型,攻击类型,离子供应,固化溶液度和温度.
- 使用Sobol灵敏度分析来确定每个因素对扩张的影响.
主要成果:
- 硫酸盐含量是影响SACA扩张的主要因素,表现出与应变的对数关系.
- 需要至少0.5%的硫酸含量才能启动扩张;扩张在1%以下是轻微的,并且在1-3%和5%以上的硫酸含量之间遵循不同的阶段.
- 较高的硫酸盐含量,较高的紧缩和较低的温度与膨胀正相关,而水泥含量的影响是不一致的. 石膏的攻击比硫酸的攻击要慢. 加高促进了1%以上的硫酸盐含量扩张.
结论:
- 硫酸盐含量是SACA扩张的主要驱动因素,观察到特定的值和菌株发展阶段.
- 压缩和温度等因素显著影响膨胀,需要在材料设计和施工中仔细考虑.
- 内部硫酸盐攻击导致比外部攻击更大的扩张,突出了材料采购和保护策略的重要性.
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