泡沫混凝土改性试验与分析

为分析发泡剂掺量、粉煤灰掺量对试件抗压强度、吸水率、导热系数、干密度的影响,开展了泡沫混凝土的配制和粉煤灰改性试验。结果表明,随发泡剂掺量增加,泡沫混凝土试件的强度、吸水率、干密度呈下降趋势,发泡剂掺量为1.25%时,泡沫混凝土试件的导热系数为0.2105 W/(m·K)、吸水率为18.3%,均达到最低值;随粉煤灰掺量增加,改性试件的强度下降、吸水率提高,导热系数和干密度均先升后降;粉煤灰掺量低于30%时,微集料效应明显;若提高粉煤灰掺量,会形成更多水化物,使导热系数下降。复合改性时,掺加碳纤维可提高试件强度,但若掺量过多,则会导致强度逐步下降;导热系数随碳纤维掺量的增加逐步下降。改性前后,各组试件的性能均满足规范要求。

Testing and Analysis of Foamed Concrete Modification

In order to analyze the effect of the amount of foaming agent and fly ash on the compressive strength,water absorption,thermal conductivity and dry density of foamed concrete,the preparation and testing of foamed concrete and fly ash modified foamed concrete were carried out.The results show that the strength,water absorption and dry density of foamed concrete specimens decrease with the increase of foaming agent.When the amount of foaming agent is 1.25%,the thermal conductivity of foamed concrete specimen is 0.2105 W/(m·K),and the water absorption is 18.3%,both of which reach the lowest value.With the increase of fly ash content,the strength of fly ash modified foamed concrete specimens decreases,the water absorption rate increases,and the thermal conductivity and dry density increase first and then decrease.When the fly ash content is less than 30%,the micro-aggregate effect is obvious.If the amount of fly ash is increased,more hydrate will be formed to reduce the thermal conductivity.When compounding,the carbon fiber can increase the strength of the test specimens,but if the cutting parameters are too much,the strength will gradually decrease.The thermal conductivity of the composite modified test specimens will gradually decrease with the increase of the carbon fiber amount.Before and after the modification,the performance of all the test specimens meets the requirements of the specification.