Abstract: Plant fibers have the characteristics of light weight, high specific strength and high elongation at break, which can improve the shortcomings of concrete such as easy cracking, low tensile strength and brittle damage. At the same time, plant fibers can improve the thermal insulation properties and durability of concrete. First of all, the chemical composition and mechanical characteristics of various commonly used plant fibers were analyzed, and the modification methods of plant fibers were also discussed. Then, the researches of domestic and foreign scholars on mechanical properties, hydration characteristics, thermal insulation properties and other properties of plant fiber reinforced concrete were analyzed and summarized in detail. And the following conclusions are drawn: when using plant fibers to enhance the strength of concrete, the long fiber lay-flat method has the best effect on the enhancement of tensile strength, while the short fiber in-mixing method has a wider range of applications, and at the same time, a variety of factors, such as fiber length, fiber content, and water-cement ratio, affect the mechanical properties of concrete; plant fibers can retard the release of heat of hydration by changing the hydration characteristics of cement, thus enhancing the crack resistance of mass concrete; plant fibers can improve the thermal insulation properties and durability of concrete, and reduce the cracking of concrete through the endotrophic effect of plant fibers on concrete.

Key words: plant fiber, concrete, mechanical property, hydration characteristic, thermal insulation property