页岩陶粒预湿处理对轻集料混凝土的强度和抗冻性的影响

研究了页岩陶粒经不同程度预湿处理后轻集料混凝土强度和抗冻性(采用快冻法)的变化规律，研究结果表明：随着页岩陶粒预湿程度的增加，轻集料混凝土早期强度明显降低，后期强度变化不大，而强度增长率明显增大。随着页岩陶粒预湿程度的增加，轻集料混凝土的抗冻性有所降低，但仍能满足300次冻融循环要求。煮沸处理的页岩陶粒混凝土，含气量为4％时，经300次冻融循环，相对动弹性模量仍达85％以上；提高含气量达5％时，页岩陶粒预湿程度对轻集料混凝土的抗冻性的影响不大。同时对抗冻机理做了初步探讨。

EFFECT OF PRE-WETTED SHALE CERAMSITE ON STRENGTH AND FROST-RESISTANCE OF LIGHTWEIGHT AGGREGATE CONCRETE

The variance of strength and frost resistance (by accelerated freezingthawing) of lightweight aggregate concrete were investigated when shale ceramsite is pre-wetted in different degrees. The results show that as pre-wetting degree increases, the compressive strength of the lightweight aggregate concrete at an early age decreases severely, and that at a later age has no obvious change. However, the strength growth rate obviously increases. The degree of shale ceramsite pre-wetting affects the frost-resistance of shale ceramsite concrete to some extent, and frost-resistance the decreases; but it can still endure 300 freezingthawing cycles. After the shale ceramsite has been boiled, the relative dynamic modulus of concrete, of which the air content is 4%, is not lower than 85% after 300 freezingthawing cycles. When the air content is 5%, the degree of shale ceramsite pre-wetting has a slight effect on the frost-resistance of lightweight aggregate concrete. The freezingthawing destructive mechanism was also investigated.