混凝土碳化深度检测方法的比较
Bei Li1,2, Ye Tian3, Guoyi Zhang4
1Nanxun Innovation Institute, Zhejiang University of Water Resources and Electric Power, Hangzhou, 310018, China.
Scientific reports
|November 15, 2023
概括
这项研究比较了混凝土碳化检测方法. 热重力测量分析 (TGA) 和里埃变换红外光谱 (FTIR) 等定量方法显示的碳化程度比Phenolphthalein指标 (PI) 更深.
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.
- 分析化学 分析化学
背景情况:
- 混凝土碳化是一个关键的降解过程,影响耐用性.
- 精确检测碳化深度对于结构评估和维护至关重要.
- 现有的方法在灵敏度和适用性上有所不同,需要进行比较研究.
研究的目的:
- 综合评估和比较各种混凝土碳化检测技术的优势和应用.
- 用一种方法组合来确定混凝土样本中的碳化深度.
- 为优化混凝土碳化检测策略提供见解.
主要方法:
- 使用Phenolphthalein指标 (PI) 进行定性评估.
- 使用的定量方法:热重力测量分析 (TGA) 和定量碳酸分析 (CA).
- 应用的定性/半定量方法:X射线相位分析 (XRD) 和里埃变换红外光谱法 (FTIR).
主要成果:
- 量化方法 (CA,TGA) 和光谱方法 (FTIR,XRD) 测量碳化深度比Phenolphthalein指标 (PI) 大2-3倍.
- TGA提供了Ca(OH) 2和CaCO3.3的度分布.
- FTIR发现了标志性C-O功能组峰值,表明了碳化深度.
结论:
- 甲胺指标 (PI) 可能低估了混凝土碳化深度.
- 像TGA,XRD和FTIR这样的先进方法提供了更敏感和更准确的碳化评估.
- 这些发现支持选择适当的方法,以可靠地检测混凝土碳化.
相关概念视频
Carbonation Shrinkage
140
Atmospheric CO2 penetrates the concrete's pores and, in the presence of moisture, forms carbonic acid, which then reacts with calcium hydroxide in the hydrated cement, forming calcium carbonate. This process reduces the concrete's volume and is termed carbonation shrinkage.
The concrete's permeability is slightly reduced as calcium carbonate produced during the reaction fills its pores. Furthermore, its strength is slightly enhanced as the water released during the reaction...
The concrete's permeability is slightly reduced as calcium carbonate produced during the reaction fills its pores. Furthermore, its strength is slightly enhanced as the water released during the reaction...
140
Measurement of Air Content in Concrete
154
Air content measurement in concrete is critical for ensuring structural integrity and durability of concrete structures, especially in environments prone to severe weather conditions. Accurate air content analysis optimizes concrete's resistance to freeze-thaw cycles and enhances its workability and strength. Several methods are standardized under ASTM guidelines to measure the air content in fresh concrete, each suitable for different concrete types and conditions.
The pressure method,...
The pressure method,...
154
Non-destructive Tests for Concrete Strength
122
The rebound hammer test, also known as the Schmidt hammer test, is a non-destructive technique for evaluating the hardness of concrete and, indirectly, the strength of concrete. It operates on the principle that the rebound of a spring-driven mass from a concrete surface correlates to the surface's hardness. The device comprises a mass within a tubular housing, a spring mechanism, and a plunger that strikes the concrete. Upon release, the energy imparted to the mass by the spring causes it...
122
Testing Water Quality
114
When the quality of water for concrete preparation is uncertain, its impact on the setting time of cement and compressive strength of mortar is assessed by comparison with de-ionized or distilled water benchmarks. American Society for Testing and Materials (ASTM) C1602 requires the setting times to be within 90 minutes of the control, British Standard (BS) 3146:1980 allows a 30-minute variance in the initial setting, while British Standards European Norm (BS EN) 1008 specifies initial setting...
114
Total Voids in Concrete
117
Total voids in concrete encompass gel water volume, capillary pores, and entrapped air. Gel water (retained within the cement hydration products) and physically entrapped or adsorbed water are significant for the hydration process. For complete hydration, it's estimated that the space needed for the products of a cubic centimeter of cement doubles. Capillary pores constitute the unoccupied space within the hydrated cement paste, with their size largely influenced by the water-to-cement...
117
Abrasion Resistance of Concrete
138
Abrasion resistance is an essential characteristic of concrete that determines its durability and longevity under various wear conditions. Concrete surfaces are vulnerable to different types of abrasion. For instance, surfaces may wear down due to the constant movement of vehicles or be eroded by solids carried in water, as seen in concrete canal linings. Specific tests are conducted to measure the abrasion resistance of concrete.
One such test is the revolving disc test, where three plates...
One such test is the revolving disc test, where three plates...
138


