磨细矿渣和粉煤灰掺量对混凝土弯曲疲劳性能的影响

Influence of dosages of ground granulated blast-furnace slag and fly ash on flexural fatigue performance of concrete

将磨细矿渣和粉煤灰分别等量取代水泥得到的3组磨细矿渣混凝土和2组粉煤灰混凝土进行了弯曲疲劳试验,与基准混凝土的疲劳性能进行了对比.并由差热热重试验和恒温箱干燥高温炉灼烧法,分别测得了Ca(OH)2质量分数和非蒸发水质量分数随混凝土中磨细矿渣或粉煤灰掺量的变化规律.结果表明,对于养护龄期为90d的C50混凝土,当S95级磨细矿渣或Ⅰ级粉煤灰等量取代水泥质量的30%时,混凝土的弯曲疲劳性能最佳.

The flexural fatigue experiments of concretes containing different proportions of GGBS （ground granulated blast-furnace slag） or fly ash were carried out. In order to analyze and interpret the results of flexural fatigue tests, differential scanning calorimetry-thermal gravimetric analysis （DSC-TGA） and an ignition method with an advance dryness in stove were also completed. The mass fractions of Ca（OH）2and non-evaporable water referred to the original mass of sample were obtained from these methods. According to the results of flexural fatigue and thermal analysis, it is shown that the concrete containing 30% mass fraction of GGBS or fly ash equal-substituted for cement at age of 90 d has the superlative flexural fatigue performance.