纤维增强氯氧镁水泥砂浆弯曲韧性研究

Study on Flexural Toughness of Fiber Reinforced Magnesium Oxychloride Cement Mortar

为提高基准氯氧镁水泥砂浆强度,同时改善其弯曲韧性,将聚丙烯纤维和钢纤维以单掺和混掺两种方式掺入氯氧镁水泥砂浆中,测试了砂浆试块的抗折抗压强度,对其进行弯曲试验,绘得荷载-挠度曲线图。结果表明:掺入聚丙烯纤维和钢纤维一方面能提高基准氯氧镁水泥砂浆强度,当单掺0.5%聚丙烯纤维或单掺1%钢纤维或混掺1%钢纤维和0.75%聚丙烯纤维时,对镁水泥砂浆强度提高幅度最大;另一方面能改善基准镁水泥砂浆的抗弯拉韧性,当单掺0.75%聚丙烯纤维或单掺1%钢纤维或混掺1%钢纤维和0.75%聚丙烯纤维时,对镁水泥砂浆韧性改善效果最好。对比发现钢纤维比聚丙烯纤维对基准镁水泥综合性能提高效果好。

In order to improve the flexural toughness of magnesium oxychloride cement and increasing its mortar＇s strength, adding different content of polypropylene fibers and steel fibers into magnesium oxychloride cement in two different ways： separate incorporation and mixed incorporation, testing the flexural strength and the compressive strength of its mortar test block, carrying out the bending test and then drawing the final load-deflection curve. The results show that the incorporation of polypropylene fibers and steel fibers on the one hand can raise strength of the benchmark magnesium oxchloride cement mortar. When mixed with 0.5% polypropylene fiber or 1% steel fiber separately or simultaneously mixed with 1% steel fiber and 0.75% polypropylene fiber, the increasing effect on strength of the magnesium cement mortar was the best; The incorporation of polypropylene fibers and steel fibers on the other hand can improve the flexural toughness of the benchmark magnesium oxchloride cement mortar. When mixed with 0.75% polypropylene fiber or 1% steel fiber separately or simultaneously mixed with 1% steel fiber and 0.75% polypropylene fiber, the increasing effect on the flexural toughness of the magnesium cement mortar was the best. The improving effect of steel fibers on the comprehensive properties of magnesium cement is better than that of polypropylene fibers.