样品宽度对轻度钢筋混凝土梁中裂传播过程的影响
Hongwei Wang1,2, Hui Jin1, Zhimin Wu1
1School of Civil Engineering and Architecture, Zhejiang University of Science and Technology, Hangzhou 310023, China.
Materials (Basel, Switzerland)
|November 27, 2024
概括
本研究介绍了钢筋混凝土断裂的3D模型,揭示了2D模型高估了初始负载. 3D方法准确地模拟了裂传播,这对于理解结构分析中样本宽度效应至关重要.
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
- 计算力学 计算力学 计算力学
背景情况:
- 现有的混凝土断裂二维模型忽略了样品宽度效应,这些效应在裂传播中很重要,特别是在钢筋混凝土梁中.
- 在预先破裂的混凝土梁中,沿厚度方向的裂纹长度变化需要比2D模型提供更全面的分析.
研究的目的:
- 通过3D数值模拟,研究样品宽度对轻钢混凝土梁的断裂行为的影响.
- 开发和验证一种3D数值方法,用于模拟曲下钢筋混凝土的裂传播.
主要方法:
- 基于断裂力学的3D数值模拟被用于模拟轻钢筋混凝土梁中的裂纹传播.
- 非线性弹元素的特点是混凝土软化和钢混凝土结合滑动行为.
- 裂纹的开始被最大应力强度因子定义为达到混凝土的断裂性.
主要成果:
- 在三点曲形梁中模拟裂传播,显示计算和实验负载裂口开口位移曲线之间的良好一致.
- 3D模型表明,2D模型在初始加载阶段预测了显著更高的外部负载.
- 分析强调了样品宽度对预测的断裂行为和承载能力的重大影响.
结论:
- 开发的3D数值方法准确地模拟了钢筋混凝土的断裂,捕捉了受样本宽度影响的裂传播.
- 与2D模型相比,3D建模提供了更现实的评估,在断裂条件下对钢筋混凝土梁的行为.
- 精确模拟裂传播对于可靠的结构设计和分析至关重要,特别是对于宽度效应明显的组件.
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