改性玉米秸秆纤维素在砂浆中的应用研究

The application research of modified corn straw cellulose in cement mortar

利用改性玉米秸秆纤维素与纤维素醚复配砂浆保水增稠材料,分析了保水增稠材料中改性玉米秸秆纤维素用量对砂浆工作性、力学性能及耐久性的影响。实验结果表明:随改性玉米秸秆纤维素在保水增稠材料中用量的增加,砂浆保水率比和14 d粘结强度比先升高后降低,7 d和28 d抗压强度比逐渐增大,28 d收缩率比和冻融质量损失率、强度损失率均先减小后增大,改性玉米秸秆纤维素在保水增稠材料中用量为30%时效果最佳。微观测试表明,添加含有合适比例改性玉米秸秆纤维素保水增稠材料的砂浆硬化体孔隙率较低,结构致密,无害孔比例较高,多害孔比例较低。

Water-retaining admixture contains modified corn straw cellulose and cellulose ether, the influence of modified corn straw cellulose of different proportions on the workability, mechanical property and durability of mortar were studied. The results showed that：with the increase of proportion of modified corn straw cellulose in water-retaining admixture,the water retaining ratio and binding strength ratio of 14 d firstly increase and then decrease,the ratio of shrinkage of 28 d and loss rate of weight and strength firstly drop and then increase,and the rate of 7 d and 28 d strength were increased gradually. It was concluded that the best proportion of modified corn straw cellulose in water-retaining admixture was 30%. Microscopic test showed that the porosity of mortar mixed appropriate modified corn straw cellulose was lower, the cementitious materials exhibit more intense structure,more harmless pore and less harmful pore.