自式空气混凝土 - 测量测量测试的状态方程
Yuri S Karinski1, Vladimir R Feldgun1, David Z Yankelevsky1,2
1National Building Research Institute, Technion, Haifa 3200003, Israel.
Materials (Basel, Switzerland)
|February 24, 2024
概括
这项研究确定了高压下自化有氧混凝土 (AAC) 的状态方程. 在动态负载场景中确定了最大能量吸收的最佳AAC密度.
科学领域:
- 材料科学 材料科学 材料科学
- 地质技术工程 地质技术工程
- 固体力学 固体力学是什么
背景情况:
- 自化空气混凝土 (AAC) 是一种轻质材料,在冲击吸收方面具有潜在的应用.
- 了解其在极端压力下的行为对于先进的工程设计至关重要.
- 关于AAC高压三轴行为和状态方程 (EOS) 的现有数据是有限的.
研究的目的:
- 在高三轴压力下,实验性地确定各种自气混凝土 (AAC) 密度的状态方程 (EOS).
- 为了研究AAC在高达大约500MPa的压力下的三轴行为.
- 为了确定最佳的AAC密度用于能量消耗应用.
主要方法:
- 使用定制制造的高压三轴装置进行了度测试.
- 测量了不同AAC密度的压力-散量应变关系.
- 开发了一种新的数据处理方法,以考虑样本缩短并准确确定限制压力.
主要成果:
- 对不同的AAC密度成功获得了实验EOS曲线,显示出良好的重复性.
- 根据密度和观察到的行为,提出了三种不同的AAC类别.
- 确定了最佳的AAC密度,在初步的动态负载测试和波传播模拟中证明了优越的能量吸收能力.
结论:
- 这项研究提供了关于AAC的高压行为及其EOS的关键实验数据.
- 确定最佳的AAC密度为保护结构中增强能量消散提供了潜力.
- 基于其EOS的AAC的动态行为和应用的进一步研究是有必要的.
更多相关视频
05:38Production and Analysis of Sporosarcina pasteurii Biocement Bricks Using Custom 3D-Printed Molds for Unconfined Compression Tests
Published on: March 7, 2025
262
06:34Operation of a 25 KWth Calcium Looping Pilot-plant with High Oxygen Concentrations in the Calciner
Published on: October 25, 2017
7.9K
相关概念视频
Measurement of Air Content in Concrete
144
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,...
144
Soundness of Cement
168
The soundness of cement refers to the ability of cement paste to retain its volume after setting. Unsound cement can lead to expansion and structural damage due to the presence of free lime, magnesia, and calcium sulfate. Free lime hydrates very slowly, expanding and causing unsoundness, which is difficult to detect because it intercrystallizes with other compounds. Magnesia also reacts with water, forming crystals that can disrupt the cement's structure. Calcium sulfate can create...
168
Strength of Cement
137
Strength tests for cement are not performed directly on neat cement paste due to difficulty in obtaining consistent, reliable specimens. Instead, cement is typically tested in the form of cement-sand mortar.
For compressive strength tests, ASTM C 109-05 standards prescribe a cement-sand mix ratio of 1:2.75 and a water/cement ratio of 0.485 for making 2-inch cubes. These cubes are mixed, cast, and cured in saturated lime water at 23°C until testing. Flexural strength testing, outlined in...
For compressive strength tests, ASTM C 109-05 standards prescribe a cement-sand mix ratio of 1:2.75 and a water/cement ratio of 0.485 for making 2-inch cubes. These cubes are mixed, cast, and cured in saturated lime water at 23°C until testing. Flexural strength testing, outlined in...
137
Porosity and Absorption of Aggregate
287
Aggregates contain pores of varying sizes; while some are completely enclosed within the particles, others open onto the surface, allowing water to penetrate. The porosity of aggregates is a major factor contributing to the overall porosity of concrete, given that aggregates constitute about three-quarters of concrete's volume.
When all pores in an aggregate are filled with water, the aggregate is considered saturated and surface-dry. If left in dry air, water will evaporate until the...
When all pores in an aggregate are filled with water, the aggregate is considered saturated and surface-dry. If left in dry air, water will evaporate until the...
287
Effects of Air-entrainment in Concrete
85
Air entrainment in concrete significantly enhances the material's durability, especially in environments subjected to freeze-thaw cycles. Introducing small air bubbles into the concrete mix acts as internal voids that accommodate the expansion of water when it freezes, thereby alleviating internal stress and preventing structural cracks. This function is crucial in climates with significant freezing and thawing, as it protects the concrete from repeated stresses that could lead to premature...
85
Dynamic Modulus of Elasticity of Concrete
331
The dynamic modulus of elasticity assesses how a concrete structure deforms under impact or dynamic loads. It is typically higher than the static modulus of elasticity, measured under slow, steady loading conditions.
The sonic test is a common method to determine the dynamic modulus. In this test, a concrete beam, sized either 6 x 6 x 30 inches or 4 x 4 x 20 inches, is clamped at its center. Vibrations are initiated at one end of the beam by an electromagnetic exciter unit powered by...
The sonic test is a common method to determine the dynamic modulus. In this test, a concrete beam, sized either 6 x 6 x 30 inches or 4 x 4 x 20 inches, is clamped at its center. Vibrations are initiated at one end of the beam by an electromagnetic exciter unit powered by...
331
