由于腐蚀分布不均,钢筋混凝土截面发生裂纹
Magdalena German1, Jerzy Pamin1
1Chair for Computational Engineering, Cracow University of Technology, Warszawska 24, 31-155 Cracow, Poland.
Materials (Basel, Switzerland)
|September 28, 2023
概括
这项研究使用有限元法模拟腐蚀诱导的混凝土断裂,揭示了由于不均的生扩张导致的钢筋周围复杂的裂纹模式. 调查结果有助于预测结构性故障和混凝土裂变.
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:
- 钢筋混凝土 (RC) 结构的腐蚀带来了重大的安全和经济挑战.
- 了解腐蚀引起的裂纹对于结构完整性的评估至关重要.
研究的目的:
- 模拟和分析混凝土中腐蚀诱导的断裂,考虑到不均的生扩张.
- 研究RC结构中的裂纹形成,传播和故障模式.
主要方法:
- 使用有限元 (FE) 方法进行数值模拟.
- 用损伤可塑性模型对混凝土进行建模,用钢作为弹性可塑性.
- 代表生作为一个模拟体积膨胀和混凝土裂纹的接口.
主要成果:
- 模拟RC截面的二维FE模型,具有不同数量的钢筋条.
- 观察到复杂的裂纹图案,特别是在侧面钢筋杆周围.
- 裂和潜在故障模式之间的预测相互作用,包括混凝土分裂.
结论:
- 不均腐蚀导致比均腐蚀更复杂的裂纹模式.
- 该FE模型有效模拟腐蚀引起的裂纹,并预测结构行为.
- 结果提供了对腐蚀RC结构的故障机制的见解.
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