含掺合料混凝土氯盐侵蚀后孔结构特征试验研究

Experimental study on influence of mineral admixture on pore structure of concrete after chloride corrosion

对氯盐侵蚀后不同掺合料混凝土进行了压汞试验,从细观角度研究了掺合料对混凝土孔结构特征的影响。结果表明:单掺粉煤灰20%、35%和50%以及单掺矿粉35%和50%,均有效降低了混凝土的总孔隙率,单掺50%矿粉时总孔隙率最小;单掺粉煤灰20%、35%以及单掺矿粉35%和50%,均有效降低了混凝土的总孔面积,单掺50%矿粉时总孔面积最小;单掺粉煤灰20%、35%和50%以及单掺矿粉35%和65%,均有效降低了混凝土的平均孔径,且单掺65%矿粉时平均孔径最小;单掺粉煤灰35%和50%及单掺矿粉65%时,最可几孔径较基准混凝土明显减小,混凝土孔径得到细化;单掺粉煤灰35%和50%以及单掺矿粉35%和65%均使多害孔、有害孔比例减小,且粉煤灰掺量在50%左右,有害孔比例最小,混凝土抗渗性能最好。

The pore structure feature of concrete mixed with mineral admixture after chloride corrosion was studied through MIP.The results showed that fly ash（20%,35%,50%）and slag（35%,50%）reduced the porosity,and the porosity was the least when the SG＇s percentage was 50%.Fly ash（20%,35%）and slag（35%,50%）reduced the total pore area,and the total pore area has a minimum value when the SG＇s percentage was 50%.Fly ash（20%,35%,50%）and slag（35%,65%）reduced the average pore size,and the value became lowest when the SG＇s percentage was 65%.Fly ash（35%.50%）and slag（65%）reduced the most probable aperture.Fly ash（20%,35%,50%）and slag（35%,65%）reduced the percentage of much harm pore and the harmful pore.When the dosage of fly ash was around 50%,the pore structure and anti-penetrability performance of concrete became best because the percentage of harmful pore was the lowest.