研究早期毛细血管压力和塑料收缩性质的高容量飞混凝土
Jintao Liu1,2, Xinyang Yu1, Shaojiang Wang3
1College of Civil Engineering, Zhejiang University of Technology, Hangzhou 310023, China.
Materials (Basel, Switzerland)
|May 7, 2025
概括
在不同温度下对高容量飞灰混凝土 (HVFAC) 塑性变形和毛细血管压力的研究有限. 这项研究发现,空气进入时间和塑料收缩量随温度的增加而增加,为混凝土裂预防提供了洞察力.
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
- 建筑技术 建筑技术 建筑技术
背景情况:
- 在不同环境温度下,对高容量飞灰混凝土 (HVFAC) 的早期塑性变形和毛细血管压力进行的研究有限.
- 了解这些特性对于防止早期裂和优化混凝土结构中固化策略至关重要.
研究的目的:
- 为了研究水结合剂比率,飞灰含量和环境温度对空气入气时间 (T),毛细血管压力 (P) 和HVFAC的塑料收缩的影响.
- 确定这些参数之间的相关性,并为减轻塑料裂变提供理论基础.
主要方法:
- 设计了九种不同的HVFAC混合物,调整了超级可塑剂剂量,以实现一致的180毫米沉降.
- 在受控温度条件下 (20°C和35°C) 进行实验分析,测量空气进入时间,毛细血管压力和塑料收缩.
主要成果:
- 在20°C时,空气进入时间 (T) 随着较高的水结合比率和飞灰含量而增加;在35°C时,这种影响是最小的.
- 高温空调的塑料收缩量随着固化温度显著增加,与空气进入时间 (T) 呈现线性相关性.
- 毛细血管压力 (P) 在低水结合比率下随温度增加,但在高比率下没有明显的趋势.
结论:
- 环境温度和混合设计参数显著影响HVFAC的早期塑性变形和毛细血管压力.
- 这些发现为开发有效策略提供了理论基础,以防止塑料裂变并优化混凝土的早期固化.
更多相关视频
05:36Production and Analysis of Sporosarcina pasteurii Biocement Bricks Using Custom 3D-Printed Molds for Unconfined Compression Tests
Published on: March 7, 2025
153
09:41Magnet Assisted Composite Manufacturing: A Flexible New Technique for Achieving High Consolidation Pressure in Vacuum Bag/Lay-Up Processes
Published on: May 17, 2018
13.4K
相关概念视频
Shrinkage in Concrete
61
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...
61
Drying Shrinkage
53
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...
53
Factors Affecting Creep
100
In normal-weight aggregate concrete, the hardened cement paste is the primary contributor to creep, whereas the aggregates, being stiffer than the cement paste, are more resilient to stress-induced deformation. The stiffness of the aggregates is defined by their modulus of elasticity, and the more voluminous they are in the concrete, the less it will creep.
Further, the water/cement ratio is critical, as a lower ratio increases concrete strength, thus reducing creep. The strength of the...
Further, the water/cement ratio is critical, as a lower ratio increases concrete strength, thus reducing creep. The strength of the...
100
Fatigue Strength of Concrete
140
Fatigue, in the context of materials science and engineering, refers to the weakening or failure of a material caused by repeatedly applied loads, even if these loads are below the strength limit of the material. Fatigue strength in concrete is a critical property that influences its durability and longevity. Concrete can fail in two ways due to fatigue. Static fatigue or creep rupture occurs under a constant load or one that increases slowly. The other failure mode is due to cyclical or...
140
Carbonation Shrinkage
93
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...
93
Superplasticizers
72
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,...
72
