冷-解周期对UHPC-RC复合柱的轴向压缩行为的影响
Shuling Gao1,2, Leyu Liu1
1School of Civil and Transportation Engineering, Hebei University of Technology, Tianjin 300401, China.
Materials (Basel, Switzerland)
|April 27, 2024
概括
超高性能混凝土 (UHPC) 钢筋混凝土 (RC) 复合体柱显示,峰值负载和模量降低,但结解周期后柔性增加. 螺杆间距显著影响性,更紧的间距提高了性能.
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
- 结构工程 结构工程
背景情况:
- 超高性能混凝土 (UHPC) 为钢筋混凝土 (RC) 结构提供了卓越的耐用性.
- 了解环境因素 (如冷解周期) 对复合体柱性能的影响至关重要.
研究的目的:
- 为了研究UHPC-RC复合体柱的轴向压缩性能,这些柱经过冷解周期.
- 为了评估不同杆间距对这些复合柱的性能的影响.
主要方法:
- 在UHPC-RC复合体柱上进行了轴向压缩测试,暴露于0,100,200和300个冷解周期.
- 测试的样本具有不同的杆间距 (35毫米,70毫米,105毫米).
- 开发了一种在融条件下承载能力的预测模型.
主要成果:
- 在整个测试过程中,UHPC外保持完整,即使在结解暴露后.
- 结解周期降低了峰值负荷和初始弹性模量,但增加了柔性.
- 增加的杆间距显著提高了复合体柱的柔性,35毫米间距显示在100个循环后,柔性系数比105毫米间距高112.6%.
- 开发的预测模型准确地反映了实验承载能力的结果.
结论:
- UHPC-RC复合体柱在冷解环境中保持结构完整性.
- 结解周期会降低机械性能,但可以通过设计修改来提高柔性,例如减少杆间距.
- 该研究提供了一个验证的模型和实验数据,用于在寒冷的气候下设计UHPC-RC复合体柱.
相关概念视频
01:23Behavior of Concrete Under Compressive Load
161
Concrete exhibits specific behaviors under different compressive loads. Understanding this is crucial for understanding its structural integrity. When concrete undergoes uniaxial compression, it tends to develop cracks that run parallel to the direction of the force. These parallel cracks stem from localized tensile stresses that occur perpendicular to the compression direction. Additionally, angled cracks may appear due to the formation of shear planes.
As the concrete specimen fractures under...
As the concrete specimen fractures under...
161
01:29Frost Resistant Concrete
77
Concrete's susceptibility to frost damage during freeze-thaw cycles demands strategic measures to enhance its frost resistance. Employing techniques like air entrainment, adjusting the water-cement ratio, proper curing, and selecting appropriate aggregates are essential.
Introducing microscopic air bubbles into the concrete mix through air entrainment creates small voids that accommodate ice expansion, thereby reducing internal pressures and preventing cracking. The optimal amount of...
Introducing microscopic air bubbles into the concrete mix through air entrainment creates small voids that accommodate ice expansion, thereby reducing internal pressures and preventing cracking. The optimal amount of...
77
01:27Frost Action on Concrete
97
Concrete structures in cold climates, such as those along roadsides, can retain moisture. This moisture makes them susceptible to frost-related damage when temperatures fall below freezing. Adding moisture worsens the damage during temperature fluctuations, leading to repeated freezing and thawing. De-icing salts, spread over these structures to melt ice, add to the freeze-thaw cycle, and draw even more moisture into the concrete.
This freeze-thaw cycle primarily causes surface scaling, where...
This freeze-thaw cycle primarily causes surface scaling, where...
97
01:25Effects of Creep
136
Creep in concrete, the gradual deformation under prolonged stress, significantly impacts the integrity of structures. For reinforced concrete beams, it can be a vital design consideration, as it increases deflection, sometimes necessitating additional design measures. In columns, especially slender ones under eccentric loads, creep can cause buckling, compromising their stability. However, creep can be beneficial in indeterminate structures by mitigating stresses that arise from shrinkage,...
136
01:17Design of Columns under a Centric Load
113
The design of columns under centric load is a fundamental aspect of structural engineering and is critical for ensuring the stability and integrity of structures. Euler's and Secant's formulas are central to understanding and calculating the critical load and deformation behaviors of columns, providing a basis for safe and effective structural design.
Euler's formula is applicable under the assumption that the column is a perfect, straight, homogenous prism, and it is operating...
Euler's formula is applicable under the assumption that the column is a perfect, straight, homogenous prism, and it is operating...
113
01:26Unsoundness of Aggregate due to Volume Change
106
Unsoundness in aggregates due to volume changes is primarily caused by the physical alterations aggregates undergo, such as freezing and thawing, thermal changes, and wetting and drying. Unsound aggregates, when subjected to these changes, result in volume change upon disintegration. This, in turn, contributes to the deterioration of concrete, including scaling, pop-outs, and cracking. Particular types of aggregates, such as porous flints, cherts, and those containing clay minerals, are...
106