粉煤灰加气混凝土收缩机理的研究

根据毛细管张力理论,多孔材料在干燥过程中,当毛细管水完全失去时,积聚在固体材料内的弹性应变能将释放,导致材料的不连续收缩。这一理论在蒸压粉煤灰加气混凝土的干燥变形过程中得到了证实,并发现这一理论在吸湿膨胀过程中同样适用。通过材料性能的综合实验研究,进一步从理论上分析了产生不连续干缩(或湿胀)变形的条件,并在此基础上建立了干燥收缩曲线方程。

STUDY ON THE SHRINKAGE MECHANISM OF FLY-ASH AUTOCLAVED AERATED CONCRETE

According to capillary tension theory, the elastic strain energy of porous materials will be released when their capillary water loses completely in the drying precess. This explains the reason of discontinuous shrinkage of porous materials, and is confirmed for the first time at drying of autoclaved fly-ash aerated concrete(F-AAC).It is also applicable to the swelling deformation of F-AAC. By further study of the properties of F-AAC, conditions causing discontinuous dry shrinkage deformation have been clarified, and the equation of the dry shrinkage of F-AAC is worked out.