水泥对大掺量磷石膏泡沫混凝土的影响

Effect of cement content on large content of phosphogypsum foam concrete

在水泥、矿粉和大掺量磷石膏的胶凝体系中以水玻璃为激发剂制备泡沫混凝土用于路基填筑。为降低水泥掺量,提高固废利用率,研究了水泥掺量对大掺量磷石膏泡沫混凝土性能的影响。结果表明,水泥最佳掺量为15%,此时泡沫混凝土的流动度为172 mm,28 d抗压强度为3.36 MPa。通过调整泡沫掺量制备出了不同湿密度的泡沫混凝土,湿密度为600、700 kg/m3时,28 d抗压强度分别为0.61、0.87 MPa,符合路基材料对泡沫混凝土抗压强度的要求;在水泥掺量为8%时,峰值放热速率和7 d放热量最大;随水泥掺量减少,在相对湿度80%条件下,泡沫混凝土呈膨胀状态,在相对湿度60%条件下,泡沫混凝土呈早期膨胀后期收缩状态。

Foam concrete was prepared by water glass as the initiator in cement,mineral powder and large amount of phosphogypsum cement for subgrade filling.And the influence of cement content on the properties of foam concrete was studied in order to further reduce the cement content and improve the utilization rate of solid waste.The results show that the optimal cement content is 15%,and the flow value and 28 d compressive strength of foam concrete are 172 mm and 3.36 MPa,respectively.At the same time,foam concrete with different wet densities was prepared by adjusting the foam content,and when the wet density was 600 kg/m3 and 700 kg/m3,the compressive strength of 28 d was 0.61 MPa and 0.87 MPa respectively,which still met the requirements of the current subgrade material for the compressive strength of foam concrete;when the cement content was 8%,the peak heat release rate and 7 d heat release were the largest.With the decrease of cement content,foam concrete expands under 80%humidity conditions,and foam concrete expands early and shrinks late under 60%humidity.