寒冷地区纤维轻骨料混凝土耐久性研究

EXPERIMENTAL STUDY ON FROST RESISTANCE DURABILITY OF POLYPROPYLENE FIBER REINFORCEMENT LIGHTWEIGHT AGGREGATE CONCRETE

采用天然浮石、聚丙烯纤维、钢纤维配制纤维轻骨料混凝土,研究其在水和盐溶液两种冻融环境中的抗冻性能。研究发现,轻骨料混凝土在硫酸钠—冻融的复合损伤明显大于单一冻融损伤。聚丙烯纤维的加入可以减缓轻骨料混凝土的强度损失,而对质量损失的改善并不明显。掺入硅灰和粉煤灰后,轻骨料混凝土的质量损失和强度损失均大幅下降,抗冻耐久性得到显著改善。

Pumice, polypropylene fiber and steel fiber were used to compound fiber reinforced lightweight aggregate concrete （LWAC）. Frost resistance durability of polypropylene fibers reinforced LWAC is studied, which includes freezing - thawing resistance in salt solution （5 % Na2 SO4 ） and in water. The results show that LWAC durability deteriorates more rapidly in salt solution than in water. The strength loss of LWAC is reduced and the mass loss of LWAC is not obvious by mixing fiber. The mass loss and strength loss of LWAC is reduced and the mass loss of LWAC is not obvious by mixing fiber. The mass loss and strength loss are decreased significantly. Introducing the fly ash and silica fume can improve frost resistance of fibers reinforcement LWAC dramatically.