含脱硫灰渣气泡混合轻质土硫酸钠耐久性试验研究

Experimental on durability of sodium sulfate on air bubble mixed lightweight soil with desulfurization ashes

为了研究含脱硫灰渣的气泡混合轻质土的耐硫酸钠腐蚀性能,设计了4组气泡混合轻质土配合比,分别置于清水与质量分数为5%,10%和15%的硫酸钠溶液中养护,对养护满28 d龄期的试样作无侧限抗压强度试验、XRD物相分析、SEM和EDS分析。试验结果表明:含脱硫灰渣的气泡混合轻质土对于硫酸钠溶液的腐蚀主要受到盐溶液浓度和脱硫灰渣含量的影响,其中盐溶液浓度的影响最大;高浓度硫酸钠溶液腐蚀下的试样存在比低浓度更强烈的AFt晶体和石膏晶体的衍射峰,按强度大小排列分别为硫酸钠浓度15%>10%>5%;低浓度的硫酸钠溶液腐蚀对轻质土的孔隙结构具有增益效果;含脱硫灰渣的气泡混合轻质土抵抗硫酸钠溶液腐蚀的阈值浓度为10%。

In order to study the durability of sodium sulfate on air bubble mixed lightweight soil with desulfurization ashes,four groups of air bubble mixed lightweight soil were designed,which were respectively cured in clear water and 5%,10%and 15%sodium sulfate solution.Unconfined compressive strength test,XRD phase analysis,SEM and EDS analysis were tested on the samples cured for 28 days.The results show that:the corrosion of air bubble mixed lightweight soil with desulfurization ashes to sodium sulfate solution is mainly affected by the concentration of salt solution and the content of desulfurization ashes,in which the concentration of salt solution has the greatest influence;the diffraction peaks of aft crystal and gypsum crystal with higher concentration of sodium sulfate solution are stronger than those with lower concentration,and the order of intensity is 15%of sodium sulfate concentration the results show that the corrosion of low concentration sodium sulfate solution has a gain effect on the pore structure of light soil,and the threshold concentration of air bubble mixed lightweight soil with desulfurization ashes to resist the corrosion of sodium sulfate solution is 10%.