弯曲应力作用下钢纤维混凝土氯离子侵蚀性能

Chloride Ion Corrosion of Steel Fiber Concrete under Bending Stress

研究弯曲应力作用下钢纤维混凝土的氯离子侵蚀性能,分析了钢纤维掺量、弯曲应力水平对混凝土氯离子含量、氯离子扩散系数的影响规律。结果表明,钢纤维的存在能改善弯曲应力作用下的氯离子侵蚀性能,钢纤维掺量为1. 5%时,改善效果最明显。弯曲应力的存在加速了氯离子在钢纤维混凝土中的扩散速度、增大了混凝土氯离子含量,应力水平越大时影响越明显。钢纤维混凝土氯离子扩散系数与应力水平间存在指数型数学关系式,最终建立了钢纤维混凝土氯离子扩散系数随应力水平变化的数学模型。

The performances of chloride ion corrosion of steel fiber concrete under bending stress were studied. The influence of steel fiber addition and bending stress level on chloride ion content and diffusion coefficient of concrete were analyzed. The results show that steel fiber can improve the performances and the improvement effect is most obvious with the steel fiber content is 1.5%. The diffusion rate of chloride ions in concrete is accelerated and the chloride ion content is increased under bending stress. It is found that there is an exponential mathematical relationship between chloride ion diffusion coefficient and stress level of steel fiber concrete. Based on the experiments and analysis, a mathematical model for the variation of chloride ion diffusion coefficient with stress level of steel fiber concrete is established.