Study On Macroscopic Properties And Engineering Application Of Cement-Based Fiber Composite Blanket

Cement-based fiber composite blanket has rapid solidification forming,simple and convenient construction,flexible and diverse specifications and good waterproof,fire,corrosion resistance.It is of great significance to apply cement-based fiber composite blanket to some construction projects with strict requirements on machinery,manpower,time and cost,such as slope protection of cofferdam,lining of ditch,reinforcement and repair of structure.At present,there are few theoretical researches on cement-based fiber composite blanket,and the related applications lack of theoretical support,which affects the extensive promotion and application of this material.Therefore,this paper mainly carried out experimental research on mechanical properties and durability of cement-based fiber composite blanket,and carried out engineering practice exploration for a dam slope protection project.The main conclusions are as follows:（1）The woven characteristics of three-dimensional spacer fabric used for cement-based fiber composite blanket determine that it has a clear direction,longitude along the length direction,weft along the width direction,silk parallel distribution along the longitude direction,cross distribution along the weft direction.The mesh size of fabric mesh surface affects the particle size of the filling material.The cement mortar dry powder prepared by ordinary Portland cement and mechanical sand with particle size ≤1.18 mm as the matrix can achieve good filling.The unique sprinkler forming process of cement-based fiber composite blanket can ensure that the cement matrix in the 10 mm thick cement-based fiber composite blanket can be fully hydrated and coagulated and hardened,and the amount of water on the strength of little influence.However,the forming process tends to cause more sand particles in the upper layer of cement mortar matrix and more sand particles in the lower layer of cement matrix,which has little effect on its mechanical properties.（2）The composite of cement mortar matrix and three-dimensional spacer fabric can significantly improve the mechanical properties of cement-based fiber composite blanket.The tensile strength of cement-based fiber composite blanket is significantly affected by the distribution of fibers.The zonal tensile strength is 1.25 times that of the longitudinally tensile strength,and the failure modes along the zonal and longitudinally are obviously different.The interaction between cement matrix and fiber is more obvious in the process of bending failure due to the distribution of fiber.（3）The volume deformation of cement mortar matrix in cement-based fiber composite blanket is obviously constrained by fibers,and affected by the distribution law of fibers along warp and weft directions,the shrinkage deformation of cement mortar matrix is significantly smaller than that of cement mortar matrix under natural curing condition,and the warp dry shrinkage deformation is less than that of weft direction.Cement-based fiber composite blanket has good freezing resistance and soaking drying cycle resistance.（4）Cement fiber composite blanket is convenient in construction of cofferdam slope protection project,without the use of large construction machinery and a lot of labor,especially suitable for inconvenient transportation and labor shortage projects.The cement base fiber compound blanket is manually laid on the spot and is hardened by sprinkling water or soaking water directly.After hardening molding,it has a high fitting degree with the surface of the soil slope,good integrity,and can adapt to the deformation of the soil slope.Experience rain and snow weather,can effectively resist erosion,do not produce settlement.It can be widely applied to such projects with uneven foundation and soft foundation.