新型双膨胀源膨胀剂的研究

Study on a new style expansive agent with two expansive sources

以普通硅酸盐水泥熟料、石膏和石灰为原料制成膨胀源为钙矾石和Ca(OH)2的新型双膨胀源膨胀剂,并与普通膨胀剂做对比实验。新型双膨胀源膨胀剂的最优配比为m(水泥熟料:)m(石膏):m(石灰+硬脂酸)=48:32:20。其中,m(石灰):m(硬脂酸)=85:15,并粉磨10 min。结果表明:新型双膨胀源膨胀剂在掺量为8%～12%且标养条件下,试样具有良好的膨胀效果,且膨胀率随掺量的增加而增长;同样条件下,掺新型双膨胀源膨胀剂的膨胀率大于普通膨胀剂。掺8%～12%膨胀剂的试块强度大于水泥净浆,其中以双膨胀源膨胀剂最优,并随掺量的增加力学性能略有降低。该新型膨胀剂复合GB 23439—2009《混凝土膨胀剂》要求。

A new compound expansive agent with two expansive sources of ettringite （C3A＊3CaSO4＊32H2O） and Ca（OH）2 was prepared by taking ordinary silicate clinker, gypsum and lime as raw materials,and the comparison was made between the new style expansive agent and ordinary expansive agent. The optimum formula of the new style expansive agent was as follow： re（silicate clinker） ：m （gypsum） ：m （lime＋stearic acid） =48：32：20. In which, m （lime） ：m （stearic acid） =85：15, and grinding for 10min. The results showed that the new style expansive agent had a good expansive property when it was the addition of 8%-12% under standard curing condition,and the expansion rate increased with addition content added. Under the same conditions,the expansion rate of the new compound expansive agent is larger than normal expansive agent. The strength of samples with 8%-12% expansive agent was better than cement paste,and the new style expansive agent had the best strength performance among them. The mechanical strength had a slight decline with the adding of expansive agent content. The new style expansive agent meets the requirements specified in standard GB 23439--2009 ＂Concrete Expansive Agent＂.