现代混凝土增韧防裂原理及应用

从水泥基体和增强纤维两个方面综述混凝土增韧防裂的原理，分析增韧防裂技术的影响因素和作用效果，介绍了典型应用工程。从分子、微观和细观三个层次，阐述了纳米材料、有机高分子材料和聚合物对水泥基体增韧的作用机制。从纤维 基体界面作用力、裂缝形成和非稳态扩展抑制等方面，论述纤维种类和特性对混凝土硬化前后阶段增韧防裂的作用规律。基体增韧与纤维增韧相结合，能够提高混凝土的抗拉强度、拉伸应变和断裂能，并有效降低裂缝宽度，抑制裂缝扩展。

Toughening and crack prevention of modern concrete: mechanisms and applications

From the two perspectives of cement matrix and reinforcing fiber, the principles of concrete toughening and crack prevention are reviewed, and then the influencing factors and the effects of toughening and crack prevention technologies are analyzed, together with the introduction of some typical applications. From the molecular, microscopic and mesoscopic levels, the mechanisms of the toughening of cement matrix by applying nanomaterials, organic polymer materials and polymers are explained. From the aspects of fiber-matrix interfacial bonding strength, crack formation and non-steady state crack propagation suppression, the effects of fiber types and characteristics on the toughening and crack prevention of concrete before and after its setting and hardening are discussed. The combination of matrix toughening and fiber toughening can increase the tensile strength, tensile strain and fracture energy of concrete, effectively reduce the width of cracks and restrain crack propagation.