硫酸盐腐蚀对混杂纤维混凝土弯曲韧性的影响研究

发布时间：2018-11-08 16:32

【摘要】：为了研究混杂纤维混凝土经硫酸盐腐蚀后的弯曲性能,首先对不同掺量的聚乙烯纤维(PE)与聚丙烯粗合成纤维(HPP)混凝土进行了硫酸盐干湿循环腐蚀和长期浸泡腐蚀试验,然后以三分点弯曲试验为基础,结合美国ASTMC1018和奥地利ORS评价方法,对比分析了混杂纤维混凝土在硫酸盐腐蚀前后其弯曲韧性变化及最佳纤维掺量。结果表明,纤维的掺入使得混凝土的破坏类型发生了变化,破坏时的最大荷载和挠度均明显增大,混凝土I_5、I_(10)、I_(20)、R_(5,10)和R_(10,20)显著提高,韧性水平也明显高于普通混凝土;在硫酸盐腐蚀作用后不同纤维掺量的混凝土其弯曲韧性均出现了不同程度的下降,其中干湿循环腐蚀条件下比长期浸泡腐蚀条件下的混凝土的弯曲韧性受损更为严重;聚乙烯纤维(PE)与聚丙烯粗合成纤维(HPP)掺量为0.8%~1.2%的混凝土在经受450 d长期浸泡腐蚀作用后的I_5、I_(10)与R_(5,10)值分别提高了32.2%、19.6%和6.8%,具有良好的耐硫酸盐腐蚀性能和弯曲韧性。
[Abstract]:In order to study the flexural properties of hybrid fiber concrete after sulphate corrosion, the sulphate dry and wet cycle corrosion tests and long term immersion corrosion tests were carried out for polyethylene fiber (PE) and polypropylene coarse synthetic fiber (HPP) concrete with different contents. Then the flexural toughness and the optimum fiber content of hybrid fiber reinforced concrete before and after sulphate corrosion were compared and analyzed based on the three-point bending test combined with the evaluation method of ASTMC1018 and Austrian ORS in the United States. The results show that the failure type of concrete is changed with the addition of fiber, and the maximum load and deflection of concrete are obviously increased, and the concrete I _ 5, I _ (10), I _ (20) are obviously increased. R _ (5N _ (10) and R _ (10 ~ (10) ~ (20) were significantly increased, and the toughness level was obviously higher than that of ordinary concrete. After sulphate corrosion, the flexural toughness of concrete with different fiber content decreased to different degrees, and the flexural toughness of concrete under dry and wet cycle corrosion condition was more serious than that under long-term immersion corrosion condition. When the content of polyethylene fiber (PE) and polypropylene coarse synthetic fiber (HPP) is 0.8% and 1.2% respectively, the I _ S _ (5) I _ (10) and R _ (5N) _ (10) values of concrete after 450 days of immersion corrosion have been increased by 32.2%, respectively. 19.6% and 6.8%, good sulphate corrosion resistance and flexural toughness.
【作者单位】：长安大学材料科学与工程学院;长安大学交通铺面材料教育部工程研究中心;陕西省交通规划设计研究院;
【基金】：国家自然科学基金项目(51508030) 青海省重大科技专项计划项目(2014-GX-A2A) 长安大学中央高校基本科研业务费专项资金(310831162001,310831161001)
【分类号】：TU528.572

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