碳纳米管增强混凝土复合材料的力学性能分析与研究

碳纳米管增强复合材料以其独特的物理性能和广阔的应用前景，近年来已迅速成为相关领域中最为活跃的研究课题。本项目将找到能够克服碳纳米管之间范德华力的方法，以单壁以及多壁纳米管作为增强材料加入到水泥基体形成碳纳米管增强复合混凝土，并观察碳纳米管在水泥基体中的存在形态、分布以及碳纳米管同水泥基体之间的粘结。并设计实验研究碳纳米管与混凝土基体之间的粘结性能，建立能够考虑这种粘结性能的力学模型。同时通过碳纳米管增强水泥的力学以及断裂性能实验，建立适合于碳纳米管增强混凝土计算模拟的本构关系，进一步将此本构关系引入Kriging无网格理论体系，推导适合于碳纳米管增强混凝土力学性能计算的新方法，Kriging无网格方法较传统无网格方法以及有限元数值求解方法，在处理结构边界条件，屈曲、断裂以及破坏等力学问题时更加优越。本研究所提出的新方法对纳米复合材料的应用及研究将具有重要意义。

With the exceptional physical and mechanical properties, and wide application prospects in industries, nano-fiber reinforced concrete has become a research hot topic in wide disciplines and continuing attract increasing worldwide attention. This proposal suggests a nano-fiber reinforced composite material mixed by carbon nanotubes and concrete. A practical method that can separate nanofibers and put these reinforcement evenly into the cement matrix. The morphology of nano-fibers in cement matrix will also be observed by high resolution electron microscope. Interface between nano-fibers and the cement matrix will also be observed. Bonding behavior between nano-fibers and cement matrix is crucial for the overall performance of carbon nano-fiber reinforced concrete, which is also investigated intensively in the proposed research. A constitutive relationship for the modeling of nano-fiber reinforced concrete will be proposed in this research and further introduced into Kriging mesh-free method, which has so many advantages in dealing with boundary conditions, buckling and fracture problems in comparison with other mesh-free approaches and finite element methods. The proposed research is expected to present a new approach for the use and simulation of nano-fiber reinforced concrete structures.