山西灵丘低硅铁尾矿制备加气混凝土的试验研究

以低硅铁尾矿作为主要原料，铝粉作为发气剂，成功制备出了符合GB/T 11968-2006的A3.5，B06级加气混凝土制品。考虑最大限度使用铁尾矿的情况下，铁尾矿、硅砂、石灰、水泥和脱硫石膏的最优化配合比(质量比)为40∶20∶25∶10∶5，铝粉加入量为0.057%，水料比为0.57，静停养护温度为70 ℃，加气混凝土制品的抗压强度达到4.11 MPa，此时体积密度为590 kg/m 3 ，比强度为6.97 MPa。由X射线衍射测试分析可知，成品中主要的矿物成分为托贝莫来石，此外还有硬石膏和残留的石英等。扫描电镜和能谱分析结果显示，成品中形成了CSH和托贝莫来石相互交织的网状结构，有效的提高了加气混凝土的强度。

Experimental study of using Shanxi Lingqiu low-silica iron ore tailings to produce aerated concrete

The samples of aerated concrete were successfully prepared in line with GB/T 11968-2006 of the A3.5,B06-class by low-silica iron ore tailings as the main raw material,aluminum powder as gas evolution agent.Iron ore tailings,silica sand,lime,cement and gypsum with the optimized ratio(mass ratio) was 40∶20∶25∶10∶5 in the case of maximizing the use of iron ore tailings,aluminum powder was added at 0.057%,water/solide ratio was 0.57,the static stop curing at 70 ℃,the compressive strength and the calculated specific strength of the finished aerated concrete samples with the bulk density of 590 kg/m3 were 4.11 and 6.97 MPa.The major mineral phases in the aerated concrete product were tobermorite with residue quartz and anhydrite.SEM and EDS results show that the finished product to form a network structure by CSH and tobermorite,the compressive strength of aerated concrete samples are effectively improved.