| 引用本文: | 饶平平,项远兵,崔纪飞,吴志林,欧阳昢晧.雷电冲击作用下土体的变形特性分析[J].哈尔滨工业大学学报,2023,55(2):125.DOI:10.11918/202203095 |
| RAO Pingping,XIANG Yuanbing,CUI Jifei,WU Zhilin,OUYANG Peihao.Analysis of deformation characteristics of soil subjected to lightning impulse[J].Journal of Harbin Institute of Technology,2023,55(2):125.DOI:10.11918/202203095 |
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| 摘要: |
| 为研究雷电冲击作用下土体的变形特性,应用冲击波理论描述雷电冲击压力,基于麦克斯韦方程推导雷电在土中产生的电磁力表达式,采用Drucker-Prager弹塑性准则,建立雷电冲击压力和电磁力作用下的土体动态变形特性有限元模型,通过瞬态计算深入探究雷击过程中土体的变形特性,并结合土中应力分布特征对变形进行动力分析,采用正交分析法研究土体力学参数对模型结果的影响以及主次因素排序,分析主要因素和雷电流峰值对模型结果的影响规律。结果表明:一定雷电冲击作用下,土体变形呈先急剧增加而后变形速率逐渐减缓,经过部分回弹后再趋于稳定,在此过程中,土中应力变化动态规律与应力波传播规律类似；土体内摩擦角和弹性模量对土体变形的影响相对较为显著,参数较小时将造成明显的变形增加,且内摩擦角的改变将影响表面土体竖向变形曲线分布规律；此外,随着雷电流峰值的增大,电磁力对土体变形的影响程度显著提升。 |
| 关键词: 雷电冲击压力 电磁力 动力响应 变形 有限元 |
| DOI：10.11918/202203095 |
| 分类号:TU435 |
| 文献标识码:A |
| 基金项目:国家自然科学基金面上项目(42077435) |
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| Analysis of deformation characteristics of soil subjected to lightning impulse |
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RAO Pingping,XIANG Yuanbing,CUI Jifei,WU Zhilin,OUYANG Peihao
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(School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai 200093, China)
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| Abstract: |
| The deformation characteristics of soil under lightning impulse were studied. The shock wave theory was used to describe the lightning impulse pressure, and the expression for the electromagnetic force generated by lightning in the soil was derived based on Maxwell′s equations. Using Drucker-Prager elastic-plastic criterion, the finite element model of dynamic deformation characteristics of soil under lightning impulse pressure and electromagnetic force was established. The transient computation was performed to investigate the deformation characteristics of soil during lightning strikes, and the dynamic analysis of the deformation was carried out by combining the stress distribution characteristics in the soil. With the orthogonal analysis method, the influence of soil mechanical parameters on the model results and the ranking of primary and secondary factors were studied, and the influence of critical factors and lightning current peak was analyzed. Results show that under the action of lightning impulse, the deformation of soil increased sharply at first, then slowed down gradually, and tended to be stable after partial springback. In this process, the stress distribution in the soil was similar to the stress wave propagation. The internal friction angle and elastic modulus within the soil had more significant effect on the deformation, and a smaller value could cause a significant increase in deformation. The change in internal friction angle also affected the distribution law of vertical deformation curve of surface soil. In addition, the influence of electromagnetic force on soil deformation increased significantly with the increase in the peak value of lightning current. |
| Key words: lightning impulse pressure electromagnetic force dynamic response deformation finite element |
