【摘要】 研究了三种加气混凝土（水泥-石灰-砂、水泥-矿渣-砂和水泥-石灰-粉煤灰）在人工碳化条件下的行为。 用红外光谱法分别测定完全碳化的三类加气混凝土吸收的CO₂的量,发现水泥-石灰-粉煤灰吸收的CO₂量小于另两类加气混凝土。但是,粉煤灰加气混凝土的碳化速度明显高于另两类。对完全碳化的样品的强度测定表明,与未碳化样品相比,粉煤灰制品碳化后强度下降的幅度大于另两类。 此外,在碳化过程中红外吸收峰由表征水化硅酸钙的Si—O键向硅胶的Si—O键逐渐转变。 合成了几种纯矿物,并比较了它们在人工碳化条件下的碳化速度,发现结晶度低的水化硅酸钙的碳化速度高于结晶完好的托勃莫来石,这有助于说明为什么粉煤灰加气制品的碳化速度高于另两类加气混凝土。 用扫描电镜-能谱研究了碳化前后的加气混凝土样品。此项研究对于说明在碳化进行的过程以及碳化后样品仍能保持强度以启示。更多还原

【Abstract】 The behavior of three types of AAC（cement-lime-sand, cement-slag-sand and cementlime-flyash） exposed to CO₂ in artificial enviroments has been studied.In fully carbonated samples, the amount of CO₂ absorbed by cement-lime-flyash AAC as determined by infrared spectroscopy is smaller than that absorbed by the other two types of AAC in the study. However, the rate of carbonation is higher for AAC from flyash and when fully carbonated, its strength is reduced to a greater extent than that of the other two types.The gradual shift of the IR absorbing peak of samples in the course of carbonation from one characterizing the Si—O bond in calcium silicate hydrate to the one in SiO₂ gel has also been studied.Pule compounds have been synthesized and their rate of carbonation compared. The higher rate of carbonation of synthetic poorly crystallized calcium silicate hydrates as compared with that of synthetic tobermorite may be helpful in explaining the rapid carbonation of the AAC made from flyash.SEM-EDAX observation on samples prior to and after carbonation reveals the process of carbonation and the strength of the samples retained after carbonation.更多还原