|
| 热-力耦合作用下混凝土劈拉动态力学性能及数值模拟研究 |
| Dynamic Mechanical Properties and Numerical Simulation of Concrete Splitting under Thermal-Mechanical Coupling |
| 投稿时间：2025-07-14 修订日期：2025-10-26 |
| DOI： |
| 中文关键词: SHPB 高温 动态劈拉性能 细观有限元 |
| 英文关键词: split hopkinson pressure bar high temperature dynamic cleaved performance mesoscopic finite elements |
| 基金项目:安徽省高校自然科学重点项目(2024AH050261)；矿山地下工程教育部工程研究中心开放基金(JYBGCZX2023101)。 |
|
| 摘要点击次数: 150 |
| 全文下载次数: 0 |
| 中文摘要: |
| 为探究高温后C50混凝土劈拉动态力学性能及微观特性，利用高速摄像仪和SHPB（Split Hopkinson Pressure Bar，分离式霍普金森压杆）试验装置，通过动态劈拉试验分析了温度（20~600℃）与应力率（150~300GPa·s-1）热-力耦合作用对材料力学行为的影响，揭示了C50混凝土在试验范围内劣化机理；基于细观有限元数值模拟，分析了ITZ（Interface Transition Zone,骨料-水泥界面过渡区）细观损伤主导的破坏现象。试验及数值模拟结果表明：温度与应力率耦合作用下C50混凝土动态劈拉强度与温度呈线性负相关，与应力率呈线性正相关；数值模拟计算结果与试验吻合，具有良好的一致性；ITZ的优先损伤与裂纹水平扩展导致试件破坏，裂纹沿骨料边缘水平扩展；提出热-力耦合作用下混凝土强度预测模型fd=0.025σ-0.0138T+6.998。该研究成果促进了高温后混凝土多场耦合机制的研究，为经历高温后的混凝土结构抗冲击性能优化与安全评定给予理论支撑。 |
| 英文摘要: |
| To investigate the post-thermal dynamic behavior and microstructural evolution of C50 concrete under high-temperature exposure, the influence of thermal-mechanical coupling of temperature (20~600°C) and stress rate (150~300GPa·s-1) on the mechanical behavior of C50 concrete was analyzed by using a high-speed camera and SHPB (Split Hopkinson Pressure Bar) test device, and the deterioration mechanism of C50 concrete within the test range was revealed. Based on the mesoscopic finite element numerical simulation, the mesoscopic damage-dominated failure phenomenon of ITZ (Interface Transition Zone) was analyzed. The experimental and numerical simulation results show that the dynamic splitting strength of C50 concrete is linearly negatively correlated with temperature and positive correlation with stress rate under the coupling effect of temperature and stress rate. The results of the numerical simulation agree with the experiment, showing good consistency. The preferential damage of the ITZ and the horizontal propagation of the crack lead to the failure of the specimen, and the crack propagates horizontally along the edge of the aggregate. The prediction model regarding the thermal - mechanical coupling strength of concrete in the test range is fd=0.025σ-0.0138T+6.998. This research achievement promotes the study of multi-field coupling mechanisms in concrete after high temperatures, providing theoretical support for optimizing the impact resistance and safety assessment of concrete structures that have experienced high temperatures. |
|
View Fulltext
查看/发表评论 下载PDF阅读器 |
| 关闭 |
