钢筋混凝土临界锈胀力预测的双K断裂模型  

Prediction Model for Critical Expansion Force of Reinforced Concrete Based on Double K Fracture Parameters

作　　者：王显利[1] 冷冰[1] 齐春玲[1] 

机构地区：[1]北华大学,吉林132013

出　　处：《东北林业大学学报》2008年第4期48-50,共3页Journal of Northeast Forestry University

基　　金：吉林省教育厅"十一五"规划项目(2006-084)

摘　　要：应用混凝土断裂理论,结合混凝土存在初始裂缝和微缺陷的特性,假定混凝土内部钢筋表面位置沿径向存在两条初始裂纹,导出了应力强度因子的近似解析解。通过应力强度因子与锈胀力的关系建立了基于双K断裂参数的保护层初裂和完全开裂时刻的临界锈胀力预测模型,进而提出了考虑界面间隙和钢筋锈损厚度的混凝土结构锈胀开裂耐久寿命预测方法,为钢筋混凝土结构锈蚀损伤耐久寿命预测提供了一种新的理论方法。对不同的初始裂缝长度将临界锈胀力的预测值与实验结果进行比较,证实了预测模型的有效性,并对临界锈胀力的主要影响因素做了分析。An approximate analytical solution for stress intensity factor is deduced by assuming that there are two radial initial cracks on diametrically opposite sides at the steel/concrete interface in accordance with the existence of exiguous flaw and initial crack in concrete before load acting on RC structures by the fracture mechanics theory of concrete. A prediction model for critical expansion force is established in terms of the relationship between the stress intensity factor at the crack tip and corrosion expansion force based on double K fracture parameters. Thereby, a new theoretical method is proposed considering both the thickness of pore band around the steel/concrete interface and the thickness of the corroded steel. The validity of the model is verified by available experimental data, and the main factors influencing critical corrosion expansion force are analysed.

关 键 词：混凝土 断裂韧度 临界锈胀力 耐久寿命 

分 类 号：TU528.571[建筑科学—建筑技术科学]