Optimization of corn straw fiber preparation process and rheological properties of modified asphalt mastic
XIE Dandan
WANG Kun
LI Qiangfei
SUN Xingchen
JIANG Ziyu
TANG Liang
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 fiberrange analysisvariance analysisasphalt masticrheological property
Publication Date：2025-09-30
Online Publishing Date：2026-05-22(First online date of this platform, not the publication date of the document)
Pages：9( 62-70 )