徐世烺, 陈超, 李庆华, 赵昕. 超高韧性水泥基复合材料动态压缩力学性能的数值模拟研究[J]. 工程力学, 2019, 36(9): 50-59. DOI: 10.6052/j.issn.1000-4750.2018.03.0147
引用本文: 徐世烺, 陈超, 李庆华, 赵昕. 超高韧性水泥基复合材料动态压缩力学性能的数值模拟研究[J]. 工程力学, 2019, 36(9): 50-59. DOI: 10.6052/j.issn.1000-4750.2018.03.0147
XU Shi-lang, CHEN Chao, LI Qing-hua, ZHAO Xin. NUMERICAL SIMULATION ON DYNAMIC COMPRESSIVE BEHAVIOR OF ULTRA-HIGH TOUGHNESS CEMENTITIOUS-COMPOSITES[J]. Engineering Mechanics, 2019, 36(9): 50-59. DOI: 10.6052/j.issn.1000-4750.2018.03.0147
Citation: XU Shi-lang, CHEN Chao, LI Qing-hua, ZHAO Xin. NUMERICAL SIMULATION ON DYNAMIC COMPRESSIVE BEHAVIOR OF ULTRA-HIGH TOUGHNESS CEMENTITIOUS-COMPOSITES[J]. Engineering Mechanics, 2019, 36(9): 50-59. DOI: 10.6052/j.issn.1000-4750.2018.03.0147

超高韧性水泥基复合材料动态压缩力学性能的数值模拟研究

NUMERICAL SIMULATION ON DYNAMIC COMPRESSIVE BEHAVIOR OF ULTRA-HIGH TOUGHNESS CEMENTITIOUS-COMPOSITES

  • 摘要: 该文基于HJC本构模型,采用分离式霍普金森杆(SHPB)压杆系统,对掺有聚乙烯醇(PVA)纤维的超高韧性水泥基复合材料(PVA-UHTCC)的动态压缩力学性能进行了数值模拟研究。首先,通过系统分析确定了21项HJC本构参数,并验证了模拟的正确性。基于此,通过分析5组应变率下材料的动态压缩应力-应变曲线讨论了峰值应力动态增强因子DIF的应变率效应,并通过LS-DYNA软件探讨了破坏过程、破坏形态与应变率的关系。模拟结果表明:随着应变率的增加,PVA-UHTCC材料的动态压缩应力-应变曲线呈现由应变硬化主导向着损伤软化主导的转变趋势;此外,PVA-UHTCC峰值应力动态增强因子DIF具有明显的应变率效应,其值随着应变率增加而增加,且在不同应变率区间呈现不同敏感性;通过量化DIF这种分区敏感性,提出了适用于PVA-UHTCC材料的DIF与应变率对数lgε分段函数式;同时,通过对比钢纤维增强水泥基材料(SFRCC)和普通混凝土材料,发现PVA-UHTCC材料的DIF应变率敏感性较低。最后,通过LS-DYNA软件模拟试件裂缝扩展和压碎破坏过程,更好地理解了PVA-UHTCC材料动态压缩破坏行为。

     

    Abstract: Investigates the dynamic compressive behavior of PVA fiber reinforced ultra-high toughness cementitious-composites (PVA-UHTCC) using Split Hopkinson Pressure Bar (SHPB) test based on HJC constitutive model. Firstly, 21 parameters of HJC model are determined and the numerical simulation is verified. Then dynamic compressive stress-strain curves under 5 different strain rates are obtained for analyzing the strain-rate effects on Dynamic Increase Factor (DIF). The failure modes of specimens under different strain rates are also researched. The results show that with the increase of strain rate, DIF increases and the strain-hardening dominated behavior will transform into a strain-softening dominated behavior. Besides, PVA-UHTCC shows an obvious different strain-rate sensitivity in the different range of strain rates. Thusly, a functional expression between DIF and lgε is proposed. Compared with Steel Fiber Reinforced Cementitious Composites (SFRCC) and normal concrete, PVA-UHTCC has a lower strain-rate sensitivity. Finally, the crack propagation mechanism and failure modes are observed at LS-DYNA software to furtherly understand the dynamic compressive behavior of PVA-UHTCC.

     

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