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Experimental and theoretical investigation of the failure behavior of a reinforced concrete target under high-energy penetration

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Acta Mechanica Sinica 2020年第1期36卷 116-129页

作者： Fanlin Meng Tianbao Ma xiangzhao xu State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China

The dynamic mechanical properties of concrete and reinforced concrete targets subjected to high-speed projectile impact loading have a significant influence on the impact resistance of protective *** this study,high-speed projectile penetration and perforation of concrete and reinforced concrete structures was carried out to determine the high-energy impact *** failure behaviors of projectile penetration and perforation of the concrete and reinforced concrete targets were investigated,and the destruction characteristics of the targets were *** analytical model was established using the principle of minimum potential *** results show that the theoretical predictions are consistent with the experimental data,indicating that the energy method is effective for predicting the dynamic mechanical properties of concrete and reinforced concrete targets under high-speed projectile penetration.

关键词： Reinforced concrete Penetration Analytical model Failure behavior

A theoretical model of rigid projectile perforation of concrete slabs using the energy method

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Science China(Technological Sciences) 2018年第5期61卷 699-710页

作者： xu xiangzhao MA TianBao WANG ZhiHua State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology Institute of Applied Mechanics and Biomedical Engineering Taiyuan University of Technology

Projectile perforation of concrete slabs will produce numerous concrete fragments on the rear face of the concrete slabs. These concrete fragments will cause serious secondary damage to the indoor personnel and equipment of protective *** evaluating the damage area of concrete slabs is an important problem. Therefore, a theoretical model of a rigid projectile perforation of concrete slabs is constructed using the energy method in this paper. In this model, a new shear failure method is proposed to calculate the energy consumption of the shear formation by combining with the von-Mises failure criterion and failure strain. Based on the energy conservation and principle of minimum potential energy, explicit equations for the perforation performance are formulated. The theoretical predictions agree well with the experimental results. Furthermore,experiments on a high-speed projectile normal perforation of concrete are carried out to verify the accuracy of the corresponding theoretical prediction.

关键词： concrete shear plugging normal perforation principle of minimum potential energy energy conservation

A special numerical method for fluid-structure interaction problems subjected to explosion and impact loading

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Science China(Technological Sciences) 2020年第7期63卷 1280-1292页

作者： NING JianGuo MENG FanLin MA TianBao xu xiangzhao State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

A three-dimensional(3D) embedded Eulerian-Lagrangian method is proposed to simulate the 3D fluid-structure interaction(FSI) problems subjected to explosion and impact loading. This method achieves a high-quality calculation of fluid and structure deformation by adding Lagrangian particles to Eulerian grids. The overall computational domain is solved by the Eulerian method, and the Lagrangian particles with specified volume and influence domains are used to track structural deformations. The bidirectional mapping of physical quantities is achieved using the weighted average of the influence domain, which are based on the topological relationship between Eulerian grids and Lagrangian particles. Then, the data dependence solution and parallel algorithm realization are presented for the large-scale numerical calculations of explosion and impact problems. Additionally, the corresponding parallel program is developed based on the message passing interface(MPI) standard, and the parallel efficiency of parallel hydrocode are tested. The numerical results of typical explosion and impact problems are compared with corresponding experimental data to verify the effectiveness of the method. These comparisons show that the embedded EulerianLagrangian method successfully combine the advantages of both the Eulerian and Lagrangian methods to efficiently calculate the processes of large deformation and dynamic damage to the materials. The results presented in this work provide a useful reference point for further research on explosion and impact problems.

关键词： explosion and impact embedded Eulerian-Lagrangian method fluid-structure interaction numerical simulation

Empirical model of concrete block fragment behavior under explosion loads

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Science China(Technological Sciences) 2024年第8期67卷 2515-2529页

作者： YANG Shuai NING JianGuo REN HuiLan xu xiangzhao State Key Laboratory of Explosion Science and Safety Protection Beijing Institute of TechnologyBeijing 100081China

Concrete structures undergo integral fragmentation under explosion loads. The fragmentation degree and particle-size distribution of concrete blocks under explosion loads must be considered during mining to ensure safety. In this study, the impulse is calculated based on the relationship between overpressure and time, and the impact energy of the explosion wave is obtained based on blast theory. Subsequently, the Mohr-Coulomb shear strength fracture criterion is introduced to determine the ultimate shear stress of the concrete materials, and an empirical model that can effectively calculate the energy consumption of concrete blocks under explosion loads is established. Furthermore, concrete fragments with different particle sizes under explosion scenarios are quantitatively predicted with the principle of energy conservation. Finally, explosion tests with different top standoff distances are conducted, and the concrete fragments after the explosion tests are recovered, sieved, weighed, and counted to obtain experimental data. The effectiveness of the fragment empirical model is verified by comparing the model calculation results with the experimental data. The proposed model can be used as a reference for civil blasting, protective engineering design, and explosion-damage assessment.

关键词： concrete structures explosion loads fragment behavior empirical model

A mass abrasion model with the melting and cutting mechanisms during high-speed projectile penetration into concrete slabs

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Acta Mechanica Sinica 2022年第10期38卷 14-27页

作者： Jianguo Ning Huilan Ren Zhao Li xiangzhao xu State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China China North Vehicle Research Institute Beijing100072China

In this study,ogive-nose projectile penetration into concrete slabs was tested at initial projectile impact velocities ranging from 1325.0 m/s to 1425.0 m/*** depth of penetration and mass loss of the projectiles were measured,and the residual projectiles were recovered after the penetration *** electron microscopy and metallographic microscopy of the microstructures were performed on various sections and outer surfaces of the projectiles taken from different locations of the residual projectiles,to analyze the intrinsic mechanisms of mass *** analysis results reveal that,during high-speed projectile penetration,projectile abrasion is caused by multiple *** on the cavity expansion theory,a projectile penetration model was established by considering the two main mass loss mechanisms observed in the microscopic *** theoretical predictions of the penetration depth,mass loss rate,and change of projectile head are consistent with the experimental results obtained both in this study and previous research.

关键词： Projectile abrasion Microscopic observation High-speed penetration Concrete target

弹体高速冲击载荷下钢筋混凝土的破坏行为实验与细观数值模拟

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中国科学：技术科学 2021年第3期51卷 259-271页

作者：荣誉任会兰许香照北京理工大学爆炸科学与技术国家重点实验室北京100081

钢筋混凝土在土木工程与国防领域具有广泛而重要的应用,且存在明显的尺寸效应,有必要进行大尺寸侵彻实验研究其在高速冲击下的动态响应.本文开展了100 mm大口径卵形弹高速侵彻钢筋混凝土靶的实验,并对靶体的破坏模式、侵彻深度和开坑直... 详细信息

钢筋混凝土在土木工程与国防领域具有广泛而重要的应用,且存在明显的尺寸效应,有必要进行大尺寸侵彻实验研究其在高速冲击下的动态响应.本文开展了100 mm大口径卵形弹高速侵彻钢筋混凝土靶的实验,并对靶体的破坏模式、侵彻深度和开坑直径进行了详细分析.由于钢筋的加入导致混凝土具有更为复杂的非均质性和各向异性,各组分的变形、破坏和相互作用对混凝土力学特性产生重要的影响.基于Voronoi技术提出了一种钢筋混凝土三维细观快速并行建模方法,解决了骨料大规模投放以及钢筋和骨料交叉检测的难题,并结合K&C模型对实验工况进行了细观数值模拟,得到了靶体和钢筋的破坏模式、弹体侵彻深度以及弹道偏转,实验结果与数值模拟结果吻合良好,说明该细观模型能够有效和准确地预测钢筋混凝土的破坏行为.

关键词：钢筋混凝土高速侵彻快速并行建模细观数值模拟

大口径聚能装药侵彻厚混凝土靶板的数值模拟及实验研究

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中国科学：技术科学 2016年第4期46卷 339-348页

作者：许香照马天宝郝莉北京理工大学爆炸科学与技术国家重点实验室北京100081 北京建筑大学理学院北京100044

采用自主开发的软件平台EXPLOSION-2D对不同锥角药型罩结构的聚能装药成型进行数值模拟,并得到了聚能装药成型规律以及炸高对聚能装药侵彻厚混凝土靶板的影响.基于侵彻体的性能参数选取了两类侵彻效果较好的聚能装药结构进行侵彻厚混凝... 详细信息

采用自主开发的软件平台EXPLOSION-2D对不同锥角药型罩结构的聚能装药成型进行数值模拟,并得到了聚能装药成型规律以及炸高对聚能装药侵彻厚混凝土靶板的影响.基于侵彻体的性能参数选取了两类侵彻效果较好的聚能装药结构进行侵彻厚混凝土靶板的数值模拟研究.根据侵彻结果设计了一种侵彻厚混凝土靶的聚能装药结构,并进行了相应的实验研究.对实验后混凝土靶板进行剖切,通过混凝土靶的内部破坏情况评估侵彻体对不同位置处混凝土靶的损伤情况,并测量各个位置处的孔洞直径.采用EXPLOSION-2D软件平台对实验工况进行模拟,对比分析实验与数值模拟的结果.对比结果表明该数值模拟技术能够有效地评估混凝土靶板的破坏情况.

关键词：聚能装药深侵彻混凝土数值模拟

冲击波强间断的高分辨率低耗散的精确捕捉数值计算方法

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中国科学：技术科学 2024年第5期54卷 870-880页

作者：宁建国苏璇许香照北京理工大学爆炸科学与技术国家重点实验室北京100081

强间断是爆炸冲击波的典型特征之一,如何高效且高分辨率地求解爆炸冲击波强间断是实现爆炸冲击问题精确数值模拟的关键.本文基于传统5阶加权本质无振荡(weighted essentially non-oscillatory,WENO)格式提出一种具有更高分辨率、更低耗... 详细信息

强间断是爆炸冲击波的典型特征之一,如何高效且高分辨率地求解爆炸冲击波强间断是实现爆炸冲击问题精确数值模拟的关键.本文基于传统5阶加权本质无振荡(weighted essentially non-oscillatory,WENO)格式提出一种具有更高分辨率、更低耗散的5阶WENO格式.通过引入一种紧凑形式的局部光滑度量对子模板的光滑度进行定量表征,并设计新的全局光滑度量以衡量整体模板的光滑度,能够充分利用各子模板的光滑信息,有效降低强间断附近的耗散.针对现有格式的权值调控系数受网格步长直接限制的缺陷,提出一种能够摆脱网格步长依赖的自适应权值调控系数,使得非线性权值能够随流场变化自动调控.此外,该权值调控系数适当地提高欠光滑模板的权重,避免在网格较粗糙的情况下将欠光滑部分误识别为强间断,从而提高格式分辨率.最后,通过精度测试与典型的具有强间断特性的数值算例表明新计算方法可明显降低强间断附近的耗散,提高传统WENO格式的分辨率,从而实现对爆炸冲击波的锐利捕捉以及冲击波碰撞后复杂流场旋涡结构的高分辨率识别,为爆炸冲击问题的数值模拟仿真和冲击波强间断面的预测提供支撑.

关键词：强间断光滑度量因子高分辨率低耗散

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弹体贯穿混凝土数值模拟的改进材料模型

爆炸与冲击 2022年第11期42卷 77-89页

作者：任会兰荣誉许香照北京理工大学爆炸科学与技术国家重点实验室北京100081

研究混凝土结构在冲击载荷下的力学特性对武器以及防护结构的设计和评估具有重要意义,而合适的材料模型可以更准确地预测混凝土结构的力学行为和破坏模式。因此,本文中提出了一种改进的混凝土塑性损伤材料模型来描述其在冲击载荷下的力... 详细信息

研究混凝土结构在冲击载荷下的力学特性对武器以及防护结构的设计和评估具有重要意义,而合适的材料模型可以更准确地预测混凝土结构的力学行为和破坏模式。因此,本文中提出了一种改进的混凝土塑性损伤材料模型来描述其在冲击载荷下的力学响应。该改进模型考虑了压力-体积应变关系、应变率效应、洛德角效应和塑性损伤累积对混凝土材料力学特性的影响,并引入了一个与损伤相关的硬化/软化函数来描述压缩状态下的应变硬化和软化行为。随后,通过对3个独立的强度面进行线性插值得到了该改进模型的破坏强度面,并采用部分关联流动法则考虑了混凝土材料的体积膨胀特性。最后,开展了单个单元在不同加载条件下和弹体贯穿钢筋混凝土靶的数值模拟,验证了该改进模型的可行性、准确性以及预测性能提升。

关键词：混凝土冲击载荷材料模型硬化/软化函数塑性损伤累积

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