Laboratory Investigation of Brucite Fiber in Stabilizing and Reinforcing Asphalt Binder

Abstract

The purpose of this study is to evaluate brucite fiber's properties, stabilizing and reinforcing effects, and corresponding mechanism when used for asphalt binder. Commonly used fibers such as lignin fiber, basalt fiber, and polyester fiber were chosen for comparative studies. Laboratory tests of water absorption, oven heating, and mesh-basket draindown were designed and performed to evaluate their wettability, thermostability, asphalt absorption, and stabilization, respectively. The cone penetration test was applied to study the resistance to shear of fiber modified asphalt; the standard dynamic shear rheometer test was conducted to evaluate the rheological properties and rutting resistance of fiber modified asphalt; and Scanning Electron Microscopy (SEM) analyses was introduced to observe fiber's microstructure characteristic and its spatial network in asphalt binder. The results indicate that brucite fiber has improved the moisture susceptibility property and thermostability more than lignin fiber. It has better asphalt absorption and stabilization effects than basalt fiber and polyester fiber. Meanwhile, brucite fibers can effectively improve asphalt binder's resistance to rutting and shear, and dynamic shear modulus. Brucite fiber can effectively reinforce the asphalt matrix through its functions of spatial networking, adhesion and stabilization of asphalt binder.