地聚合物基超高性能混凝土抗弹丸侵彻性能试验与模拟

With the development of the national defence, there is an increasingly higher requirement for concrete materials to resist blast and impact loadings in protective structures. Meanwhile, more attention is being paid to green concrete materials which are less energy intensive and more eco-friendly. This project investigates the impact resistance of an eco-friendly geopolymer-based ultra-high performance concrete using high-velocity ogive-nosed projectile penetration tests. Since the addition of fibres and coarse aggregates enhances the fracture toughness and hardness of concrete materials, which could further improve the impact resistance, this project also explores the influence of fibres and coarse aggregates such as types and dosages on the impact performance of the geopolymer-based ultra-high performance concrete. In order to comprehensively understand the dynamic damage and failure mechanism of the geopolymer-based ultra-high performance concrete, an approach of numerical simulations is used to ensure the suitable material model and algorithm. With the validated numerical models, parametric studies are then conducted to obtain the depth of penetration under various scenarios, and an empirical or semi-empirical equation is proposed to predict the depth of penetration based on the simulation data as well as the test results. The outcomes of this project are of great significance to design and promote the structural components or structures made of eco-friendly geopolymer-based ultra-high performance concrete to resist high-velocity projectile penetration, which will lay a solid foundation for the further research on the new protective materials in this area.

随着国防事业的不断发展，防护工程领域对于混凝土材料的抗爆炸抗冲击性能要求越来越高。同时，国家对环保问题的愈发重视促使低能耗高环保的绿色混凝土材料成为研究工作的重点。本项目以环保型地聚合物基超高性能混凝土为研究对象，通过高速尖头弹侵彻实验，来测试其抗侵彻性能。由于纤维和粗骨料的添加会相应地增强混凝土靶体的断裂韧性和硬度，从而增强其抗侵彻能力，因此本项目拟探究不同纤维和粗骨料的种类与含量对于地聚合物基超高性能混凝土抗侵彻效果的影响。为进一步阐明地聚合物基超高性能混凝土在侵彻作用下的动态响应及损伤破坏机理，本项目同时采用数值模拟的方法来确定适合的材料本构模型以及算法，并运用参数分析研究不同工况下靶板的侵彻深度，提出一套可行的经验或者半经验公式进行预测。研究成果对环保型地聚合物基超高性能混凝土构件和结构的抗侵彻设计以及推广具有重要的指导意义，从而为今后新型防护材料的抗侵彻性能研究打下了坚实的基础。

在重要的基础设施结构中使用绿色环保型高性能建筑材料已经成为我国防护工程领域现阶段亟需解决的关键问题。本项目研发制备了一种地聚合物基超高性能混凝土材料，通过一系列现场实验和数值模拟的方法，探究了其抗弹体高速侵彻性能，主要研究内容和意义如下：.（1）研发制备了一种碱激发地聚合物基超高性能混凝土材料（单轴抗压强度超过140 MPa，抗折强度超过20 MPa），总结了不同纤维类型、长度和体积含量对G-UHPC抗压和抗弯强度的影响规律。.（2）开展了一系列弹体高速侵彻地聚合物基超高性能混凝土靶体实验，阐明了地聚合物基超高性能混凝土在高速弹体侵彻作用下的动态响应和损伤破坏机理。.（3）从应力面、损伤、状态方程和应变率效应等方面着手，修正了常用的两种混凝土材料本构模型（KCC模型和HJC模型）用于地聚合物基超高性能混凝土，并与已有静态和弹体侵彻实验数据进行了对比分析，验证了修正后的混凝土材料本构模型和三维有限元模型的可靠性。.（4）基于有效的地聚合物基超高性能混凝土材料本构和三维有限元模型，开展了大量参数化分析，揭示了弹体速度、质量、直径、弹头形状和混凝土单轴抗压强度等关键参数对地聚合物基超高性能混凝土靶板抗侵彻性能的影响程度，建立了一套能够准确预测弹体侵彻深度和地聚合物基超高性能混凝土靶体贯穿极限厚度的经验公式。. 本项目的研究成果对地聚合物基超高性能混凝土在防护工程领域中防弹体高速侵彻的应用提供了重要的科学依据，具有一定的工程应用价值。