改性玉米秸秆纤维对沥青混合料性能影响及分散均匀性评价方法

李强飞¹，王琨^1*，谢丹丹¹，孙星辰¹，姜自玉¹，郭仁亮²，刘赢昌²

1.山东交通学院交通土建工程学院，山东 济南  250357；2.山东高速工程建设集团有限公司，山东 济南  250014

摘要：为研究改性玉米秸秆纤维质量分数对沥青混合料高、低温性能的影响及纤维的分散均匀性，制备改性玉米秸秆纤维质量分数分别为0、0.2%、0.4%、0.6%、0.8%的沥青玛蹄脂碎石混合料（stone mastic asphalt，SMA）-13，进行车辙试验和低温小梁弯曲试验（试验温度分别为-5、-10、-15 ℃），采用方差分析与效应量分析，并结合低温弯拉强度、弯曲劲度模量、弯拉应变的标准差和改性玉米秸秆纤维质量分数，提出玉米秸秆纤维分散均匀性指数。结果表明：改性玉米秸秆纤维在沥青混合料中的质量分数为0.4%时，SMA-13的动稳定度最大，为4 268次/mm，比未掺入改性玉米秸秆纤维的基准组增大50.4%，低温弯拉强度和弯拉应变显著提高，弯曲劲度模量降幅最小，表明其在抗弯拉强度、刚度与延性间实现最优平衡，分散均匀性指数最大，为1.042，纤维分散性最好，与高、低温试验结果一致。

关键词：改性玉米秸秆纤维；沥青混合料；高、低温性能；单因素分析；效应量分析；纤维分散均匀性指数

Effect of modified corn straw fiber on the performance of asphalt mixture and the evaluation method for its dispersion uniformity

LI Qiangfei¹, WANG Kun^1*, XIE Dandan¹, SUN Xingchen¹, JIANG Ziyu¹, GUO Renliang², LIU Yingchang²

1. School of Civil Engineering, Shandong Jiaotong University, Jinan 250357, China；

2.Shandong Hi-Speed Engineering Construction Group Co., Ltd., Jinan 250014, China

Abstract: To study the effect of the quality fraction of modified corn straw fibers on the high and low temperature performance of asphalt mixtures and the uniformity of fiber dispersion, asphalt mastic stone mixture (stone mastic asphalt, SMA) with modified corn straw fiber quality fractions of 0, 0.2%, 0.4%, 0.6%, and 0.8% are prepared. Rutting tests and low-temperature beam bending tests (-5, -10, -15 ℃) are conducted, and variance analysis (with a variance statistic of 66.47 and a probability of less than 0.000 1) and effect size analysis are performed. Combined with the standard deviations of low-temperature tensile strength, bending stiffness modulus, and tensile strain, as well as the quality fraction of modified corn straw fibers, a fiber dispersion uniformity index is proposed. The results show that when the quality fraction of modified corn straw fibers in the asphalt mixture is 0.4%, the dynamic stability is maximized at 4 268 times/mm, which is an increase of 50.4% compared to the control group without modified corn straw fibers. The low-temperature tensile strength and tensile strain are significantly improved, while the reduction in bending stiffness modulus is minimal, indicating an optimal balance between tensile strength, stiffness, and ductility. The dispersion uniformity index is maximized at 1.042, reflecting the best fiber dispersion, consistent with the results of high and low temperature tests.

Keywords: modified corn straw fiber; asphalt mixture; high and low temperature performance; single factor analysis; effect size analysis; fiber dispersion uniformity index