混凝土的分形性及其单轴应力下裂纹演化的混沌效应

Fractal Character of Concrete and Its Chaos Effect of Cracks Evolution under Axial Stress

基于分形几何、损伤力学和混沌理论研究混凝土的复杂结构和功能及其在单轴应力作用下其内部微裂纹动态演化规律和破坏特征。首先从唯象和分形角度描述混凝土裂纹的产生和扩展过程,然后,推导了混凝土损伤演化方程,划规为统一形式并检验其混沌特征,进而分析了混凝土裂纹演化的混沌效应;同时,利用混沌理论解释了单轴受压混凝土构件的破坏特征。通过研究混凝土裂纹演化的混沌效应,为混凝土破坏机理研究提供新的手段,也为混凝土结构设计和维护提供理论依据。

The complex structure and function of concrete and the dynamic evolutive laws and damage character of concrete minor cracks under axial stress are studied based on fractal geometry, damage mechanics and chaos theory. Firstly, the origin and development of concrete cracks in terms of appearance are described, then the evolutive equations of concrete damage are deduced and uniformed, their chaos character is tested. The chaos effect of concrete cracks evolution is analyzed. At the same time, the cause of the damage character of axial compress concrete component is explained in terms of the chaos theory. By the study of the chaos effect of concrete cracks evolution, the new methods of studying the laws of concrete damage are found, and thus the theoretical basis for design and maintenance of concrete structure is provided.