目前石灰石粉掺加于混凝土中用法主要为置换水泥或置换细骨料,前者会影响强度,后者主要作用仅为解决细骨料短缺问题.应用石灰石粉更合理方法为填充混凝土骨料颗粒之间的空隙,以减少需要填充骨料空隙的水泥浆量从而提高耐久性.本研究探讨了石灰石粉置换水泥浆方法对混凝土渗透性和吸水性的影响,配制了一系列混凝土试样作强度、渗水性、吸水性和孔隙率测试.结果表明,掺加石灰石粉置换水泥浆能减小混凝土可渗透孔隙,在相同水灰比下或相同强度下有效减少混凝土的渗水性和吸水性.%The present use of limestone fines in concrete is replacement materials of either cement or fine aggregate.The former type of replacement would impair the strength,while the latter type of replacement is mainly adopted where fine aggregate is not enough.The limestone fine shall be better used as cement paste replacement to reduce the cement paste volume required to fill the voids for durability improvement.To study the effect of this strategy of using limestone fines in concrete to durability,concrete specimens with different limestone fines dosage at different W/C ratio were made and their strength,permeability and sorptivity were measured.Results proved that use of limestone fines as cement paste replacement could reduce the permeable porosity,and significantly lower the permeability and sorptivity at the same W/C ratio and at the strength basis.
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