基于损伤演化方程的混凝土寿命预测方法

基于混凝土的冻融或腐蚀损伤演化方程,提出了一套预测混凝土结构使用寿命的基本方法与理论体系；用单一冻融因素作用下的大量试验数据验证了混凝土的损伤演化方程；通过专门设计的盐湖卤水腐蚀单一因素和(干湿循环+盐湖卤水腐蚀)双重因素、3.5％质量浓度的NaCl盐冻试验,研究了青海盐湖钾肥和北京城市立交桥主体结构混凝土的使用寿命预测问题.结果表明:青海盐湖钾肥工程不宜采用普通混凝土和高强混凝土；C60引气高性能混凝土在盐冻作用下满足北京城市立交桥50年的使用要求.

Predicting Method of Concrete Service Life Based on Damage Development Equation

Based on the damage development equation of concrete subjected to freezing-thawing cycles or chemical attacks,a systematic theory and the basic operation for the prediction on service life of concrete structure were presented.Validity of the damage development equation of concrete was established by the vast data obtained through single factor.Service life prediction of some national key projections,such as the potassic manure plant in salt lake of Qinghai and Beijing Cloverleaf Bridge,were studied by specially designed durability experiments,which included single factor(salt lake bittern attack),double factor(wet-dry cycles compound with salt lake bittern attack),3.5% mass concentration NaCl solution salt-frost experiments.Results show that either ordinary Portland cement concrete or high strength concrete is not applicable to the potassic manure plant in salt lake of Qinghai.Service life of Beijing Cloverleaf Bridge can also meet the requirements of 50 years since C60 air-entrained high performance concrete subjected to salt-frost action are adopted.