玉米秸秆纤维制备工艺优化及改性沥青胶浆流变性能研究

谢丹丹¹，王琨^1*，李强飞¹，孙星辰¹，姜自玉¹，唐亮²

1.山东交通学院交通土建工程学院，山东 济南  250357；2.山东省路桥集团有限公司，山东 济南  250014

摘要：为促进农业固体废弃物在道路工程中的高值化利用，提出一种玉米秸秆纤维制备及改性工艺。在NaOH与水的质量比为4%、5%、6%，蒸煮0.5、1.0、1.5 h，浸泡0.5、1.0、1.5 h的纤维改性参数条件下，基于正交试验并通过极差分析和方差分析研究改性参数对纤维吸油性与耐热性的协同影响，进行动态剪切流变和弯曲梁流变试验，测定未改性玉米秸秆纤维、改性玉米秸秆纤维、木质素纤维以及无纤维沥青胶浆的高、低温流变性能，验证玉米秸秆纤维替代木质素纤维的技术可行性。结果表明：NaOH改性处理可显著提高玉米秸秆纤维的吸油率并降低其质量损失，各改性参数对纤维吸油性和耐热性的影响程度及显著性按从大到小顺序排列依次为蒸煮时间、NaOH与水的质量比、浸泡时间；玉米秸秆纤维的最佳改性工艺组合为NaOH与水的质量比为6%、蒸煮1.5 h、浸泡1.5 h；最佳改性工艺条件下，改性玉米秸秆纤维的吸油率比木质素纤维增大1.54%、质量损失率减小84.88%；改性玉米秸秆纤维沥青胶浆的复数模量、车辙因子和松驰速率比木质素纤维沥青胶浆分别增大20.80%（48 ℃）、21.95%（48 ℃）和5.27%（-12℃），二者的蠕变劲度相当。玉米秸秆纤维用于沥青改性兼具高温稳定性与低温抗裂性，可替代木质素纤维用于沥青路面施工中。

关键词：玉米秸秆纤维；极差分析；方差分析；沥青胶浆；流变性能

Optimization of corn straw fiber preparation process and rheological properties of modified asphalt mastic

XIE Dandan¹, WANG Kun^1*, LI Qiangfei¹, SUN Xingchen¹, JIANG Ziyu¹, TANG Liang²

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

2.Shandong Province Road and Bridge Group Co., Ltd., Jinan 250014, China

Abstract: To promote the high-value utilization of agricultural solid waste in road engineering, a preparation and optimization process for corn straw fiber is proposed. Under the modification parameters of fibers with a mass ratio of NaOH to water of 4%, 5%, and 6%, and cooking for 0.5, 1.0, and 1.5 hours, as well as soaking for 0.5, 1.0, and 1.5 hours, the synergistic effects of modification parameters on the oil absorption and heat resistance of the fibers are studied based on orthogonal experiments, range analysis, and variance analysis. Dynamic shear rheology and bending beam rheology tests are used to measure the high and low-temperature rheological properties of unmodified corn straw fibers, modified corn straw fibers, lignocellulosic fibers, and fiber-free asphalt mastic, verifying the technical feasibility of replacing lignocellulosic fibers with corn straw fibers. The results show that NaOH modification significantly increases the oil absorption rate of corn straw fibers and reduces their mass loss. The degree and significance of the influence of each modification parameter on fiber oil absorption and heat resistance are arranged in descending order as follows: cooking time, mass ratio of NaOH to water, and soaking time. The optimal modification process combination for corn straw fibers is a NaOH to water mass ratio of 6%, cooking for 1.5 hours, and soaking for 1.5 hours. Under the optimal modification conditions, the oil absorption rate of modified corn straw fibers increases by 1.54% compared to lignocellulosic fibers, and the mass loss decreases by 84.88%. The complex modulus, rutting factor, and creep rate of modified corn straw fiber asphalt mastic increase by 20.80%（48 ℃）, 21.95%（48 ℃）, and 5.27%（-12 ℃）, respectively, compared to lignocellulosic fiber asphalt mastic, with both having comparable stiffness moduli. Corn straw fibers used for asphalt modification provide both high-temperature stability and low-temperature crack resistance, making them a viable substitute for lignocellulosic fibers in asphalt pavement construction.

Keywords: corn straw fiber; range analysis; variance analysis; asphalt mastic; rheological property