掺合料粉体种类对泡沫混凝土性能的影响

Influence of Filler Type on Properties of Foamed Concrete

以普通硅酸盐水泥为结合剂,用粉煤灰和硅灰取代砂和部分水泥,研究掺和料种类对泡沫混凝土抗压强度、吸水率以及抗冻性的影响。结果表明:泡沫混凝土的性能不仅与孔隙率有关,还与基体材料中掺合料的种类有关。加入硅灰可引起泡沫混凝土的成型水胶比增加,显著提高了泡沫混凝土的早期强度,但同时引起吸水率的增加,也不利于抗冻;当掺合料为粉煤灰时,提高了泡沫混凝土的抗冻耐久性,当将原状粉煤灰磨细,使泡沫混凝土的后期强度增长较快,并大幅度的降低了吸水率,但对抗冻性影响不大。

Portland cement was used as cementitious materials in developing foamed concrete, fly ash and silicon fume replaced of sand and a part of cement at the same time. The influences of the filler type on the compressive strength, water absorption and frost resistance of the foamed concrete were researched. It was shown that the properties of the foamed concrete not only concerned with porosity, but also with the filler type. When adding silicon fume, the water-solids ratio, water absorption and the strength in early stage increased sharply, but not help to frost resistance. The frost resistance of foamed concrete was improved while adding fly ash. When fly ash were grinded to fine ash, the strength in later stage increased fastly, and the water absorption decreased sharply, but the influence on frost resistance were not obvious.