西安建筑科技大学学报(自然科学版)

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.

引言
1 实验方案
2 实验结果
3 可渗透空隙对抗渗性能的影响
4 结论

表1 实验混凝土配比<br/>Tab.1 Mix design of concrete specimens

表1 实验混凝土配比
Tab.1 Mix design of concrete specimens

表2 渗水性、吸水性和强度结果<br/>Tab.2 Permeability, sorptivity and strength results

表2 渗水性、吸水性和强度结果
Tab.2 Permeability, sorptivity and strength results

图1 渗水深度随水灰比变化情况<br/>Fig.1 Variation of penetration depth with W/C ratio

图1 渗水深度随水灰比变化情况
Fig.1 Variation of penetration depth with W/C ratio

图2 渗水深度与立方体强度关系<br/>Fig.2 Variation of penetration depth with cube strength

图2 渗水深度与立方体强度关系
Fig.2 Variation of penetration depth with cube strength

图3 各配比混凝土试件单位面积渗水量随时间平方根变化情况<br/>Fig.3 Variation of water penetration amount at unit surface area with square of time

图3 各配比混凝土试件单位面积渗水量随时间平方根变化情况
Fig.3 Variation of water penetration amount at unit surface area with square of time

图4 吸水系数随水灰比变化情况<br/>Fig.4 Variation of sorptivity with W/C ratio

图4 吸水系数随水灰比变化情况
Fig.4 Variation of sorptivity with W/C ratio

图5 吸水系数与立方体强度关系<br/>Fig.5 Variation of sorptivity coefficient with cube strength

图5 吸水系数与立方体强度关系
Fig.5 Variation of sorptivity coefficient with cube strength

图6 可渗透孔隙随水灰比变化情况<br/>Fig.6 Variation of permeable pore with W/C ratio

图6 可渗透孔隙随水灰比变化情况
Fig.6 Variation of permeable pore with W/C ratio

图7 渗水深度与可渗透孔隙关系<br/>Fig.7 Variation of penetration depth with permeable pore

图7 渗水深度与可渗透孔隙关系
Fig.7 Variation of penetration depth with permeable pore

图8 吸水系数与可渗透孔隙关系<br/>Fig.8 Variation of sorptivity coefficient with permeable pore

图8 吸水系数与可渗透孔隙关系
Fig.8 Variation of sorptivity coefficient with permeable pore

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备注

引言

1 实验方案

2 实验结果

3 可渗透空隙对抗渗性能的影响

4 结论

期刊信息