ADVANCES IN ENGINEERING PROPERTIES OF FIBER REINFORCED SOIL

Fiber reinforcement is a new concept of soil improvement technique. The discrete fibers are evenly incorporated into the soil mass, which aims at improving the mechanical properties of soil. Based on the achievements at home and abroad for the past 20 years in this field, this paper presents the research progress of fiber reinforcement materials, the engineering properties of fiber reinforced soil and reinforcement mechanisms. Generally, there are two categories of fiber reinforcement materials that can be used, i.e.artificial synthetic fibers and natural fibers. On the engineering properties of fiber reinforced soil, the fiber reinforcement is effective in improving soil shear strength, compressive strength, tensile strength, bearing capacity and cracking resistance, increasing the fracture toughness and permeability of soil, reducing the swelling and shrinkage potential of expansive soil. For the fiber reinforcement mechanism, it is believed that the fiber reinforcement benefit is dominated by the interfacial mechanical interactions between fiber/soil, namely the interfacial bonding and friction force. Finally, the current research limitations in this field are discussed, and some new directions and research topics are proposed for the future work. They are development of specialized apparatus and technologies for fiber/soil mixing, development of more specialized fiber products and lower fiber costs, large-scale model tests and field tests, study on interfacial mechanical interactions between fiber reinforcement and soil, study on failure mechanisms and damage effects of fiber reinforced soil, study on mechanical model and calculation theory of fiber reinforced soil, as well as study on dynamical characteristics of fiber reinforced soil.