气凝胶含量对泡沫混凝土孔结构及性能的影响

摘要

A new type of high performance aerogel foam concrete was prepared by mechanical foaming method using cement and aerogel as gelling and filling materials respectively. The effects of aerogels ratio on the dry apparent density,thermal conductivity,water absorption and compressive strength of foam concrete were studied. The pore structure and pore size distribution of aerogels foam concrete were also characterized. The results show that the density and thermal conductivity of aerogels foam concrete are significantly lower than ordinary foam concrete,and the volumetric water absorption is also significantly reduced,for example,when add 20％ with air volume of 20％,the density of aerogel foam concrete decreased from 719 kg/m3 to 512 kg/m3,the thermal conductivity decreased from 0.188 W/(m·K) to 0.121 W/(m·K),the volumetric water absorption decreased from 37.3％ to 32.2％,and the compressive strength decreased,but still meet the strength requirements in standard JG/T 266—2011"foam concrete".%分别以水泥、气凝胶为胶凝材料和填充材料,采用机械发泡法制备了新型高性能气凝胶泡沫混凝土.研究了气凝胶含量对泡沫混凝土干表观密度、导热系数、吸水率及抗压强度的影响,表征了气凝胶泡沫混凝土孔结构及孔径分布.结果表明,气凝胶泡沫混凝土的密度和导热系数明显低于普通泡沫混凝土,体积吸水率也显著降低,当气凝胶体积含量为20％时,气凝胶泡沫混凝土的密度从719 kg/m3降低至512 kg/m3,导热系数从0.188 W/(m·K)降低至0.121 W/(m·K),体积吸水率从37.3％降低至32.2％,抗压强度虽有所降低,但仍符合JG/T 266—2011《泡沫混凝土》的强度要求.