Study On The Preparation And Performance Of Cotton Stalk Fibers In Asphalt Mixture

The fiber asphalt mixture is widely used in asphalt pavement engineering because of its excellent high temperature stability, low temperature crack resistance and resistance to the fiber asphalt mixture. At present, many types of fibers can be used for asphalt mixture, however, its preparation technologies are very complex, and the manufacturing cost is high. Cotton plants belong to malvaceae vegetation, and the straw is rich in fiber. In order to solve the problem of wasting cotton straw resource and environmental pollution, reduce the cost of existing resources, and to wide range of application of cotton stalks. This paper explores the new way of preparation of cotton stalks fiber. It is important significance to make a series of road performance evaluation.Based on cotton stalk composition and technical characteristics, the paper puts forward the cotton stalk into a kind of fiber material which can be mixed with asphalt pavement. And the paper evaluates the road performance of cotton stalk fiber. First of all, according to the structure of cotton stalk and the basic separation principle of fiber bundle, making the analysis of the adaptability of existing fiber processing equipment, the paper selects the horizontal mill grinding machine, vertical mill grinding machine, vertical plate of claw type crusher, the blade shears machine and hammer mill to prepare the proper cotton stalk fiber. Then the paper evaluates the kind of fiber. At the same time, the paper determines blade type shear machine to be processing equipment for cotton stalk fiber. Then, under different process conditions, the paper makes analysis of the differences in technical performance the preparation of cotton stalk fiber, determining the reasonable preparation technology parameters. The paper makes a comprehensive analysis of equipment selection and processing technology parameters. The optimal preparation process of cotton stalk fiber is below. Cotton stalks pretreatment---hammer---crushing--- high speed shearing dispersion---drying processing. Pretreatment stage includes preliminary crushing and shearing, soaking, hammer crushing in saturated surface dry state, and then making fiber in a state of high speed shearing dispersion in a blade type shears machine. Finally, it is concluded that the length distribution of cotton stalk fiber applied in asphalt mixture is 1~6 mm.This paper designs the test methods of oil absorption rate and thermal aging test of fiber. Furthermore, the paper evaluates its oil absorption rate and heat resistance, comparing them with lignin fiber. The results show that the oil absorption of cotton stalk fiber is slightly less than lignin fiber at high temperature for long time preservation. Cotton stalk fiber aging becomes fragile under that condition, but it still has a basic stable performance. It is a practical reference for the engineering application of cotton straw fiber in the asphalt mixture.