动态荷载与温度耦合作用下织物增强混凝土的损伤机理研究

Textile Reinforced Concrete (TRC) is a new ultra-high performance construction material with light weight, high strength and high durability, and excellent ability of strengthening and constraining cracks. Its application can significantly improve the safety and durability of existing and new engineering structures in their service life, reduce the weight of structures, and provide great flexibility in the design of green buildings. The innovative TRC and its strengthening structures have great prospects in the on-going infrastructure construction in China. The proposed project will focus on the fundamental scientific problems in the application of TRC materials. The interfacial bond properties and failure mechanism of yarns embedded in cementitious matrix under dynamic loading and varying temperatures will be investigated, and the interface bond-slip model, which considering the effects of temperatures and strain rates, will be established. Based on these results, the mechanical properties and failure mechanism of TRC material under the coupling effect of dynamic loading and varying temperature conditions will be studied. The relationship between the microstructure change and the macro-scale mechanical performance failure of TRC material under the coupling effect will be analyzed, and multiscale finite element model of TRC material will be built. This project will provide a solid theoretical foundation and technical support for the wide application of TRC material in sustainable construction in China and abroad.

织物增强混凝土（TRC）是一种新型高性能水泥基复合材料，具有轻质、高强、耐久的特性以及良好的增强和控裂性能，可提升既有和新建工程结构的安全性和耐久性，有效实现工程结构的轻量化，也可为设计绿色建筑提供极大的灵活性，新型TRC及其增强结构在我国工程建设中将会有广阔的应用前景。本项目针对应用TRC所面临的关键科学问题，研究动态荷载和不同温度下TRC材料中织物纤维束与水泥基体的界面力学性能及损伤机理，建立温度和应变率相关的界面粘结模型；在此基础上进一步研究动态荷载和温度耦合作用下TRC材料的力学性能和损伤失效机理，分析TRC在耦合作用下其微观结构变化与宏观性能损伤失效之间的关系，建立TRC材料多尺度有限元模型。本项目研究将为TRC在国内外可持续基础设施建设中的广泛应用提供坚实的理论基础和技术支撑。

织物增强混凝土（TRC）作为一种新型结构材料，急需从根本上解决一些关键科学技术问题。本项目围绕 TRC 的组成设计及多尺度力学性能等开展了深入研究。首先提出了短纤维增强、织物改性和施加预应力等显著提升 TRC 性能的新方法，突破了水泥基材料易开裂、韧性低、界面弱的缺点，建立了 TRC 材料力学行为的理论预测模型，该成果可为高性能 TRC 材料的设计和性能优化提供了理论指导。其次，揭示了冲击和温度耦合下 TRC 材料的应变硬化行为特征、纤维/基体界面及其宏观力学性能的损伤演变规律和机理。深入研究了不同纤维织物类型、不同短切纤维体积掺量（Vol.%）、不同加载速率（最高 4.5m/s）、环境条件（-50°C ~ 100°C）和织物预拉力水平对TRC力学性能影响。最终得到了材料组成、荷载及服役环境对其其关键力学性能和破坏形态的影响规律。针对推广绿色建筑的社会发展需求，研发出新型织物增强混凝土（TRC）夹芯复合墙板，并已应用于示范工程。项目资助期内发表英文SCI论文18篇，中文EI论文9篇。培养博士后1名，博士生3名（其中2在读），硕士生7人（其中1人在读）。