LiNO_3对硅质集料和白云质集料膨胀性的抑制作用

Inhibitory effect of LiNO_3 on expansion of siliceous aggregates and dolomitic aggregates

迄今为止,一直缺乏快速有效的方法来区分碱-硅酸反应活性和碱-碳酸盐反应活性。通过测定多种经过RILEM TC191-AAR-5测试检测出具有碱活性的集料在掺加硝酸锂(LiNO3)时试件膨胀率,讨论了LiNO3对硅质集料和白云质集料膨胀性的影响,为建立快速区分碱-硅酸反应活性和碱-碳酸盐反应活性的试验方法奠定了基础。试验结果表明:若集料仅存在碱-硅酸反应活性,当试件中Li/Na摩尔比为2.22,养护液中Li/Na摩尔比为1.11时,试件的28 d膨胀率可以抑制到0.1%以下;若集料为碱-碳酸盐反应活性的,掺加硝酸锂以后试件仍表现出较大的膨胀性,28 d试件膨胀率仍然超过0.1%。

So far, it had the lack of method to distinguish alkali-silica reactivity and alkali-carbonate reactivity rapidly and effectivly.Discussed the effect of lithium nitrate（LiNO3 ） on expansion of siliceous aggregates and dolomitic aggregates by testing the expansion of specimens used of several RILEM TC191-AAR-5 reactive aggregates when adding LiNO3.To some extent, it provided the basis for establishing a rapid method to distinguish alkali-silica reactivity and alkali-carbonate reactivity.It can be concluded that expansion of specimens made of aggregates only with alkali-silica reactivity was under 0.1% at 28 d when the Li/Na was 2.22 in the specimens and 1.11 in curing solution; however, expansion of speci- mens made of aggregates with alkali-carbonate reactivity was still above 0.1% at 28d at the same condition.