碱激发矿粉固化连云港软土试验研究

为了减轻使用波特兰水泥作为软土固化剂存在的高能耗、CO2排放和不可再生资源消耗等环境问题，通过室内配合比试验初步研究碱激发矿粉对连云港软土的固化效果，并与水泥固化进行对比。结果表明：Na2CO3对矿粉固化土的激发效果非常有限；NaOH激发矿粉的效果最好，7 d，28 d，90 d无侧限抗压强度最高，但是在90 d后会发生一定的强度衰减；矿粉+电石渣固化土的7 d，28 d强度比水泥固化土低，而90 d，180 d强度比水泥固化土高。Na2CO3，NaOH和Na2SO4能够加速矿粉+电石渣固化土的强度增长速率，其中，Na2CO3的效果最弱，虽然可以在90 d内提高矿粉+电石渣固化土的强度，但180 d强度反而略低；NaOH激发的矿粉+电石渣固化土强度在7 d，28 d，90 d龄期均有较大的提高，但从90 d到180 d会发生强度衰减；Na2SO4激发矿粉+电石渣的效果最好，可以在实际工程中进行应用，不仅可以减小水泥生产过程带来的环境影响，还能提高软土固化效果，降低工程造价。

TEST ON ALKALI-ACTIVATED GROUND GRANULATED BLAST-FURNACE SLAG(GGBS) FOR LIANYUNGANG SOFT SOIL STABILIZATION

In order to mitigate the environmental impacts in terms of high energy consumption，CO2 emissions and no-renewable resources consumption associated with Portland cement(PC) soft soil stabilization，the stabilization effect of alkali-activated ground granulated blast-furnace slag(GGBS) for Lianyugang soft soil was investigated through laboratory test and then it was compared with that of PC. The results show that the Na2CO3-activated GGBS had the minimum stabilization efficacy for this soft soil. NaOH-activated GGBS stabilized soil had the highest unconfined compressive strength(UCS) at 7，28 and 90 days，however its UCS decreased after 90 days. The GGBS-carbide slag stabilized soil had lower 7-day and 28-day UCS than that of PC mix，whilst the former had much higher 90-day and 180-day UCS than the latter. The Na2CO3，NaOH and Na2SO4 could accelerate the strength development rate of GGBS-carbide slag stabilized soil. The Na2CO3-activated GGBS-carbide slag stabilized soil had only slightly higher 7-day，28-day，90-day UCS and lower 180-day UCS than those without Na2CO3. NaOH significantly increased the UCS of GGBS-carbide slag stabilized soil at 7，28 and 90 days. However the UCS decrease was observed from 90 days to 180 days. The Na2SO4 had the highest activating efficacy for GGBS-carbide slag stabilized soil，and thus was suggested to use in practice due to both the economical and environmental benefits.