超吸收性聚合物尺寸对混凝土混合物的强度和收缩的影响
Wissawin Arckarapunyathorn1, Pochpagee Markpiban2, Raktipong Sahamitmongkol1
1Department of Civil Engineering, King Mongkut's University of Technology Thonburi (KMUTT), Bangkok 10140, Thailand.
Polymers
|July 30, 2025
概括
超吸收聚合物 (SAP) 颗粒大小显著影响混凝土. 较小的SAP可以提高内部固化和强度,而较大的SAP可以更好地控制收缩,这对于高性能混凝土开发至关重要.
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:
- 使用超吸收聚合物 (SAP) 进行内部固化是缓解混凝土早期裂的关键策略.
- 优化SAP特性,特别是颗粒大小,对于最大限度地提高水分和减少收缩等好处至关重要.
- 了解SAP尺寸和混凝土性能之间的关系对于开发先进建筑材料至关重要.
研究的目的:
- 研究超吸收聚合物 (SAP) 颗粒大小对混凝土机械性能和收缩行为的影响.
- 评估不同的SAP尺寸范围如何影响压力强度,弹性模量和各种收缩参数 (自生,干燥,总).
- 分析受SAP粒子大小影响的微观结构变化和化学成分.
主要方法:
- 准备五种混凝土混合物,具有不同的SAP颗粒大小分布 (150-300微米,300-600微米,600-1800微米和混合物).
- 在各种固化年龄下评估机械性能 (压力强度,弹性模量) 和尺寸稳定性 (收缩).
- 使用X射线光 (XRF) 进行微结构分析,以评估7天后化学成分的变化.
主要成果:
- 较小的SAP颗粒大小促进了更均的内部固化,增强了水化,并导致更密集的混凝土矩阵.
- 较大的SAP颗粒在减少自身和干燥收缩方面表现出更大的有效性.
- 较大的SAP颗粒大小观察到压力强度和弹性模量略有妥协.
结论:
- 选择SAP颗粒大小是平衡混凝土机械性能和收缩控制的关键因素.
- 优化的SAP尺寸分布可以导致具有显著降低裂纹潜力的高性能混凝土.
- 这项研究为针对特定性能要求的混凝土混合设计中的SAP使用量身定制提供了宝贵的见解.
相关概念视频
01:30Superplasticizers
120
Superplasticizers are advanced admixtures that enhance the workability of concrete by lowering the water content without compromising the strength of the material. These substances are highly effective water reducers, improving concrete flow, making it easier to work with, and enabling concrete to reach inaccessible areas or densely reinforced sections without mechanical vibration. The key components in superplasticizers are either sulfonated melamine or naphthalene formaldehyde condensates,...
120
01:27Shrinkage in Concrete
171
Shrinkage in concrete is primarily due to water loss from evaporation, hydration of cement, or carbonation, leading to a reduction in volume. The volumetric contraction results in volumetric strain in concrete. However, in practice, shrinkage is measured as linear strain, which is one-third of the volumetric strain.
When concrete is still in its plastic state, it can undergo a decrease in volume by about 1% of its absolute volume. This decrease is known as plastic shrinkage. It arises either...
When concrete is still in its plastic state, it can undergo a decrease in volume by about 1% of its absolute volume. This decrease is known as plastic shrinkage. It arises either...
171
01:23Pore Size Distribution
217
In concrete, the pore size distribution significantly influences the material's properties. Capillary pores, markedly larger than gel pores, form a vast network within partially hydrated cement paste, reducing the concrete's strength and increasing its permeability. This heightened permeability leads to a greater risk of damage from environmental factors like freeze-thaw cycles and chemical attacks, with the extent of vulnerability also being tied to the water-to-cement ratio.
Adequate...
Adequate...
217
01:21Drying Shrinkage
156
When hardened concrete is exposed to air with a relative humidity of less than 100 percent, it begins to lose the free water within its capillaries. As this water evaporates, the water initially adsorbed onto the calcium silicate hydrates migrates towards these now empty spaces and eventually evaporates as well. Over time, as more water leaves, the volume of the concrete decreases, a phenomenon known as drying shrinkage.
A portion of this drying shrinkage can be reversed; if the concrete is...
A portion of this drying shrinkage can be reversed; if the concrete is...
156
01:31Plasticizers
114
Water-reducers, or plasticizers, are chemical admixtures used in concrete to improve strength and workability. These additives reduce the water-cement ratio without compromising workability, lower the cement content while maintaining the same workability, or increase workability to assist concrete placement in inaccessible areas.
Plasticizers function by using surface-active agents to create repulsive electrostatic forces between cement particles. This dispersion enhances the concrete's...
Plasticizers function by using surface-active agents to create repulsive electrostatic forces between cement particles. This dispersion enhances the concrete's...
114
01:21Impact Strength of Concrete
334
Impact strength in concrete is a critical measure that reflects the material's capability to endure the forces applied during pile driving and when supporting machinery foundations that experience impulsive loads. It is also essential when handling precast concrete components to prevent accidental damage. The impact strength is assessed by observing the concrete's resistance to repeated impacts and energy absorption capacity. A key indicator of significant damage to concrete is when it...
334