通过对粉煤灰加气混凝土在不同环境条件下历经８ａ的长期观测，并结合相应的实验室冻融循环、干湿循环、以及人工和自然碳化试验研究，分析探讨了其长期强度的劣化机理。指出引起粉煤灰加气混凝土长期强度下降的主要因素是碳化，而冻融循环和干湿循环仅在一定的条件下才会加剧其强度劣化。 Through the long-term observation of fly ash aerated concrete under different environmental conditions for 8a, combined with corresponding laboratory freeze-thaw cycles, wet-dry cycles, and artificial and natural carbonation experiments, the mechanism of deterioration of long-term strength was analyzed . It is pointed out that the main factor that causes the long-term strength decrease of fly ash aerated concrete is carbonization, while the freeze-thaw cycles and the wet-dry cycles only intensify the strength deterioration under certain conditions.