纳米SiO_2对磷建筑石膏性能影响研究

本试验研究了不同掺量下纳米SiO_2对磷建筑石膏的2 h抗折强度、绝干抗折强度、2 h抗压强度、绝干抗压强度、吸水率及软化系数的影响,并通过SEM对磷建筑石膏进行微观分析。结果表明:随着纳米SiO_2掺量的增加,磷建筑石膏的抗折强度、抗压强度均呈现先上升后下降的趋势。当纳米SiO_2掺量为1%时,其对磷建筑石膏强度增强效果最好,2 h抗折强度、绝干抗折强度、2 h抗压强度、绝干抗压强度分别达到3.9MPa、8.5 MPa、14.4 MPa、24.3 MPa,较空白组分别提高14.7%、4.9%、55%、63%;随着纳米SiO_2掺量的增加,磷建筑石膏的吸水率不断降低,软化系数不断增加,纳米SiO_2掺量达到2%时,磷建筑石膏吸水率达到最低19%,较空白组降低47%;同时其软化系数达到80%,较空白组提高122%。

Study on the Influence of Nano-SiO_2 on the Performance of Phosphorus Building Gypsum

The effect of nano-SiO2 on the 2 h flexural strength, absolute flexural strength, 2h compressive strength, absolute compressive strength, water absorption and softening coefficient of nano-SiO2 on different building phosphorus was studied in this experiment. Microscopic analysis of phosphorus building gypsum. The experimental results show that with the increase of nano-SiO2 content, the flexural strength and compressive strength of phosphorus building gypsum show a trend of increasing first and then decreasing. When the content of nano-SiO2 is 1%, it has the best strength enhancement effect on phosphorus building gypsum. The 2 h flexural strength, absolute flexural strength, 2h compressive strength and absolute dry compressive strength reach 3.9 MPa and 8.5MPa respectively. 14.4 MPa, 24.3 MPa, 14.7%, 4.9%, 55%, 63% higher than the blank group;with the increase of nano-SiO2 content, the water absorption rate of phosphorus building gypsum is decreasing, the softening coefficient is increasing, and the nano-SiO2 content is increased. When it reaches 2%, the water absorption rate of phosphorus building gypsum reaches 19%, which is 47% lower than that of the blank group. At the same time, its softening coefficient reaches 80%, which is 122% higher than that of the blank group.