减水剂改性固废基蒸压加气混凝土的制备与性能研究

Preparation and properties of water reducing agent modified solid waste based autoclaved aerated concrete

以花岗岩石粉、黄河特细砂为硅质材料,以电石渣为钙质材料,以聚羧酸减水剂为改性剂,制备固废基蒸压加气混凝土(AAC)。研究了聚羧酸减水剂掺量对AAC料浆流动性、发气过程、抗压强度、干密度、孔隙率和孔径分布的影响。结果表明,减水剂掺量由0.15%增大到0.30%,料浆初始流动度、发气速率、发气量和孔隙率逐渐增大,制品抗压强度和干密度逐渐降低。减水剂掺量为0.25时,料浆初始流动性270 mm,发气量208 mL,孔隙率82.54%,抗压强度2.9 MPa,干密度509 kg/m^(3),AAC综合性能最优。减水剂掺量大于0.2%时,2 mm以上的大孔基本消失,孔隙率和孔壁无害孔含量对AAC抗压强度影响更明显。

The solid waste-based autoclaved aerated concrete(AAC)was prepared by granite stone powder and yellow river superfine sand as siliceous materials,carbide slag as calcareous material,as well as polycarboxylate superplasticizer as modifier.The effects of polycarboxylate superplasticizer dosage on paste fluidity,gassing process,compressive strength,dry density,porosity and pore size distribution of AAC were investigated.The results showed that when the water reducing agent dosage increased from 0.15%to 0.30%,the initial fluidity of the paste,the rate of gassing,the amount of gassing and porosity all gradually increased,and the compressive strength and dry density of the products gradually decreased.When the water reducing agent dosage was 0.25,the paste initial fluidity was 270 mm,the air generation was 208 mL,the porosity was 82.54%,the compressive strength was 2.9 MPa,the dry density was 509 kg/m^(3),and the overall performance of AAC was optimal.When the water reducing agent dosage was larger than 0.2%,the large pores above 2 mm almost disappeared,and the porosity and the content of harmless pores in the pore wall had a more obvious effect on the compressive strength of AAC.