为提高碳纤维在混凝土中的分散性，利用可再分散聚合物乳胶粉与短切碳纤维对混凝土进行复合改性，运用正交试验方法，基于L9(43)正交试验表，设计两批18(2×9)组聚合物乳胶粉-碳纤维复合改性混凝土(PMCFRC)的坍落度、28 d抗压强度及纤维分散性检测试验。 第1批正交试验研究了水灰比、聚合物掺量、碳纤维掺量对PMCFRC性能的影响，第2批正交试验研究了分散剂种类、分散剂掺量、减水剂掺量对PMCFRC性能的影响，获得PMCFRC的坍落度、抗压强度、电阻率等基本参数，并利用极差和方差分析方法，研究各因素的主次顺序，分析其是否影响显著，基于此寻找出PMCFRC最优配合比。结果表明：第1批正交试验中，对于坍落度、电阻率以及电阻率变动系数，碳纤维掺量为显著因素；对于28 d抗压强度，水灰比为显著因素；第2批正交试验中，对于坍落度和28 d抗压强度，减水剂掺量为显著因素；对于电阻率和电阻率变动系数，分散剂掺量为显著因素。PMCFRC最佳配合比为：水灰比0.49，聚合物掺量12%，碳纤维掺量0.3%，砂率34%，分散剂选用羟乙基纤维素，分散剂掺量0.4%，减水剂掺量1.2%，消泡剂掺量0.3%。
To improve the dispersion of carbon fiber in carbon fiber reinforced concrete, using redispersible polymer latex powder and short cut carbon fibers for composite modification of concrete, two batches of 18 (2×9) groups of polymer latex powder-carbon fiber composite modified concrete (PMCFRC) were designed based on the L9(43) orthogonal test table for the slump, 28 d compressive strength and fiber dispersion. The first batch of orthogonal tested investigated the effects of water-cement ratio, polymer admixture and carbon fiber admixture on the performance of PMCFRC. The second batch of orthogonal tested investigated the effects of dispersant type, dispersant admixture and water-reducing agent admixture on the performance of PMCFRC, obtained the basic parameters of the slump, compressive strength and resistivity of PMCFRC, and used the extreme difference and ANOVA methods respectively, the primary and secondary order of each factor was studied to analyze whether their effects were significant or not, based on which the optimal mix ratio of PMCFRC was found. The results show that in the first batch of orthogonal tests, for the slump, resistivity and resistivity coefficient of variation, the amount of carbon fiber admixture is significant factor; for 28 d compressive strength, the water-cement ratio is significant factor; in the second batch of orthogonal tests, for slump and 28 d compressive strength, the amount of water-reducing agent admixture is significant factor; for resistivity and resistivity coefficient of variation, the amount of dispersant admixture is significant factor. The optimum ratio of PMCFRC is 0.49 water/cement ratio, 12%polymer, 0.3% carbon fiber, 34% sand rate, 0.4% hydroxyethyl cellulose as dispersant, 1.2% water reducing agent and 0.3% defoamer.
秦立军, 白二雷,*, 王志航, 夏伟, 杨宁.聚合物乳胶粉改性碳纤维增强 混凝土的配合比设计[J].空军工程大学学报,2023,24(5):102-110复制