具有和没有网状增强的UHPC光束的剪切能力的新计算方法
Chuansong Gao1,2, Hui Jiang3, Gaozhan Zhang4
1BIM Engineering Center of Anhui Province, Anhui Jianzhu University, Hefei 230601, China.
Materials (Basel, Switzerland)
|November 14, 2023
概括
这项研究提出了一种新的公式,可以准确预测超高性能混凝土 (UHPC) 梁的剪切承载能力. 该公式考虑了纤维桥接和压缩区,改进了UHPC束设计的现有方法.
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
背景情况:
- 现有的超高性能混凝土 (UHPC) 梁的剪切能力计算方法往往忽略了UHPC压缩区的全部剪切贡献和纤维的概率分布.
- 这种监督导致预测UHPC梁的剪轴承能力的准确性降低.
研究的目的:
- 开发一个更准确的公式来计算UHPC梁的剪切承载能力.
- 为了更有效地结合光纤桥接效应和UHPC压缩区的剪切贡献.
- 通过实验数据验证拟议的公式,并将其准确性与现有的设计代码进行比较.
主要方法:
- 编制了一个包括247个样本的UHPC光束剪切测试数据库.
- 对剪切能力影响因素的分析,包括剪切跨度比率,网增强比率和钢纤维体积分数.
- 基于压缩区故障机制和纤维微拉伸强度的新剪切能力公式的开发.
主要成果:
- 该研究发现,UHPC梁的裂变负荷与最终负荷的比率在0.2到0.6.6之间.
- 超高压束压缩区故障被分为对角张力和剪切压缩故障.
- 当与实验数据进行验证时,拟议的公式显示了高预测准确性.
结论:
- 开发的公式准确地预测了UHPC梁的剪切承载能力,同时考虑了纤维桥梁和压缩区.
- 与当前设计代码中现有的剪切能力公式相比,拟议的公式提供了更高的预测准确性.
- 这项研究为UHPC梁的结构设计提供了更可靠的工具.
相关概念视频
01:14Shearing Stresses in a Beam: Problem Solving
200
A cantilever beam with a rectangular cross-section under distributed and point loads experiences shearing stresses. The analysis begins by identifying the loads acting on the beam. Then, the reactions at the beam's fixed end are calculated using equilibrium equations. The vertical reaction is a combination of the distributed and point loads, while the moment reaction is the sum of their moments. The shear force distribution along the beam, resulting from these loads, is established by...
200
01:22Design Example: Distributing Reinforcements in Concrete Sections
91
The topic explores the practical aspects of adjusting steel reinforcements within a concrete beam section to meet specific design requirements. When designing a reinforced concrete beam, it is essential to distribute the steel reinforcements properly to ensure structural integrity and efficiency. The example provided details a scenario where a beam requires a total steel cross-section of 4 square inches. The engineer identifies that the available steel bars have a nominal diameter of 1.693...
91
01:15Prismatic Beams: Problem Solving
118
In the design of a supported timber beam subjected to a distributed load, both the beam's physical dimensions and the timber's characteristics, such as its grade and species, are critical. These factors determine the allowable stress values, which are crucial for calculating the necessary beam depth to ensure structural integrity and safety.
The design begins with analyzing the beam as a free body to identify moments and force balances, thereby determining support reactions. Next, the...
The design begins with analyzing the beam as a free body to identify moments and force balances, thereby determining support reactions. Next, the...
118
01:16Shear on the Horizontal Face of a Beam Element
180
To understand shear on the flat side of a prismatic beam element, consider the vertical and horizontal shearing forces, and the normal forces, acting on the element. The element's upper (U) and lower (L) sections, which are divided by the beam's neutral axis, are examined. The equilibrium of these forces is determined by applying the equilibrium equation, which helps identify the horizontal shearing force. This force is directly related to the bending moments and the cross-section's...
180
01:07Unsymmetric Loading of Thin-Walled Members: Problem Solving
112
The shear center of a channel section with uniform thickness, height, and width, is determined by computing the shear force in the member and calculating the moments of inertia of the sections.
To compute the shear forces, find the shear flow at a specific distance from the endpoint using the vertical shear and the moment of inertia values. The total shear force on the flange is calculated by integrating the shear flow from one end of the flange to the other.
Next, calculate the moments of...
To compute the shear forces, find the shear flow at a specific distance from the endpoint using the vertical shear and the moment of inertia values. The total shear force on the flange is calculated by integrating the shear flow from one end of the flange to the other.
Next, calculate the moments of...
112
01:23Design of Prismatic Beams for Bending
243
The design of prismatic beams, structural elements with a uniform cross-section, focuses on ensuring safety and structural integrity under load. The design process begins by determining the allowable stress, either from material properties tables, or by dividing the material's ultimate strength by a safety factor. This safety factor is essential for accommodating uncertainties, and varies depending on the material—timber, steel, or concrete—with each having unique strength and...
243