矿物掺合料对混合骨料混凝土抗冻性能的影响

Effect of mineral admixtures on frost resistance properties of mixed aggregate concrete

将四组掺量均为30%的矿物掺合料替代水泥掺入混合骨料混凝土中,对比其抗压性能和抗冻性能。28 d立方体抗压强度试验表明:复掺20%粉煤灰和10%硅粉时,混合骨料混凝土的抗压性能最好,单掺30%粉煤灰时最差,复掺20%粉煤灰和10%矿粉优于复掺20%粉煤灰和10%石粉。冻融循环试验表明:粉煤灰与硅粉复掺时抗冻性能最高,与石粉复掺时最低,粉煤灰与矿粉复掺优于单掺粉煤灰。不掺矿物掺合料的混合骨料混凝土抗压性能与抗冻性能均优于掺加30%矿物掺合料的。

Compare the compression performance and frost resistance of four groups of mixed aggregate concrete, which were added 30% mineral admixtured respectively.The 28 d cube compressive strength tests indicate that：mixed aggregate concrete containing 20% fly ash and 10% silica fume had the best compression performance.When added in 30% fly ash,the compression performance was the worst. Concrete with 20% fly ash and 10% pulverized slag had better compression performance than that with 20% fly ash and 10% limestone powder.Freeze-thaw cycles tests showed that： when mixed with fly ash and silica fume, concrete had the best tYost resistance.While mixed with fly ash and limestone powder ,it had the lowest.Concrete with fly ash and pulverized slag had better frost resistance than that with fly ash only.Mixed aggregate concrete with mineral admixtures has worse compressive performance and frost resistance than that without any mineral admixtures.