减水剂对半水脱硫石膏现浇墙体材料性能的影响

摘要

为了拓宽脱硫石膏的利用途径，选取萘系高效减水剂( NF)、聚羧酸系减水剂( HC)、木质素磺酸钠减水剂( SM)对半水脱硫石膏现浇墙体材料进行改性研究。试验结果表明：SM 对半水脱硫石膏凝结时间影响不大，对提高石膏强度的效果与HC及 NF相比不明显；NF使得半水脱硫石膏流动性较差，不适合作为减水剂；HC对凝结时间影响较明显，对半水脱硫石膏强度提高较多，但随其掺量的增加也会产生一些不利的影响。综合考虑减水剂对墙体材料制备过程的初、终凝时间，减水率和扩展度，抗折、抗压强度的影响，选择HC作为半水脱硫石膏现浇墙体材料的减水剂，最佳掺量约为0.5%。%T he paper,with the purpose of further commercializing desulfurized plaster,selects Naphthalene agent ( NF) ,Polycarboxylic Acid agent ( HC ) and Sodium Lignosulphonate agent ( SM ) to study the material modification of cast-in-place wall with semi-hydraulic desulphation gupsum. The results indicate that SM fails to play an important role in gupsum setting,while neither HC nor NF largely influences gupsum strength. It has also been noticed that NF is yet well suited to serve as a water reducer,as it undermines the fluidity of the plaster; at the same time HC ,though visibly alters the setting time and improves the gupsum strength,exerts negative impact as its proportion adds up. Considering the agents' in fluence on initial and final setting time,water reducing ratio,spreading performance,bending resistance and compressive strength,HC with the suggested proportion of 0. 5% was chose as the preferable w ater reducer.