Experimental Research On The Mechanical Properties And Durabilities Of The Fiber Brucite Pavement Concrete Mixed With Fly Ash

Ordinary cement concrete is a kind of brittle material with more defects which is prone to structural damage under the effects of tensile,impact,vibration,bending,fatigue and so on.To improve the flexural tensile strength,crack resistance,fatigue resistance,impact resistance and other road performance of concrete,a new type of fiber reinforced concrete with excellent performance can be obtained by mixing fly ash and brucite fibers in ordinary concrete,that is brucite fiber reinforced pavement concrete mixed with fly ash.Deep research on the brucite fiber/cement-based composite materials is considered to improve the performance of cement concrete pavement and the rational unitization of dominant mineral resources.which is of great significance.The mechanical properties and durabilities of brucite fiber pavement concrete mixed with fly ash is systematically studied through laboratory contrast tests in this paper.At first,the optimal selection and the study on technical properties of raw materials and rational design of aggregate gradation are carried out according to the technical requirements of the composition materials for pavement concrete.The basic requirements on the mix design of brucite fiber reinforced pavement concrete mixed with fly ash is proposed.The method of orthogonal design is used to for the mix design of concrete combined with the calculation results of mix ratio.Range method is used to analyze the effects of different influential factors on the slump,7d and 28 d compressive strength,flexural strength of brucite fiber reinforced pavement concrete according to the results of orthogonal experiments so that a reasonable mix proportion parameters can be obtained.The optimal mix ratio of combination with the results of concrete workability test of brucite fiber reinforced pavement concrete is determined combined with the test results of concrete workability.Based on the optimal mix ratio,the researches on the effects of water-binder ratio,sand ratio,volume fraction of brucite fiber,fly ash content on the cube compressive strength,flexural strength,splitting tensile strength,impact performance,compressive modulus of elasticity and other mechanical properties,also the impermeability,frost resistance,dry shrinkage,carbonation durability of concrete are carried out in this paper.At last,the microstructure of brucite fiber reinforced pavement concrete mixed with fly ash was analyzed by SEM.