The Study On The Structure And Composition Of New Sleeper Composite Materials

As China's recoverable dwindling forest resources,timber supply gap growing,the forest logging and the use of wood processing residues get more and more attention.Development of wood residue resources to develop the new type of sleeper composite materials,on the one hand can save a great amount of timber,and make the waste that has not been fully utilized to maximize the effectiveness;On the other hand,this new material Sleeper can meet the development of amount and technical performance requirements of the high-speed railway sleeper with high research value and positive social significance.This paper firstly works out each component and structural design program of the new composite materials sleeper.DPS data processing system is used to make uniform experimental design for the experimental factors of composite materials preparation and analyze the experimental results to access he best conditions for Sleeper composite materials preparation,on the basis of which,using a Balanced Analysis of Variance(ANOVA) with Minitabl5.0,as well as the Least Significance Difference(LSD) for multiple comparisons to research the influence of three filling materials and four structure designs on the sleeper composite materials' static bending strength,modulus of elasticity,the absorbing water thickness expansion rate,the inner combination strength of dry & wet state,compressive strength,and other properties of six.The main conclusion of the study are as follows:(1) Each component of new composite materials sleeper is:wood residue for filling materials,phenolic resin(PE) for basal body,glass fiber and bamboo tablets for enhancing materials,as well as other additives including urea,parafTm solution and KH550 coupling agents.A new Sleeper composite material hasâ… ,â…¡,â…¢,andâ…£of four structural designs.(2) The experimental factors are pressing time,sizing amount and density,the best of which as:pressing time of t = 0.7min/mm;sizing amount of m = 14.30%;density of p = 0.96 g/cm³.(3) Attained the preparation conditions of the new sleeper composite materials as:hot pressing temperature T = 180 to 200℃;unit thermal pressure of P = 3.5MPa,durative unit thermal pressure of P₁= 1.9MPa,balanced unit thermal pressure of P₂= 0.3～0.5MPa; pressing time oft = 0.7min/mm;Sizing amount of q = 14.30%;density of p = 0.96 g/cm³.(4) Studied on the three filling materials(larch,poplar,mixed wood residues),four structural design(â… ,â…¡,â…¢,â…£) on the sleeper composite materials' six properties as above, confirm the mixed wood residues the best filling material and programâ…£the best designation.(5)The performances of new type of sleeper composite materials' under the best preparation conditions of all experimental factors are as follows:static bending strength for 70.26 MPa,modulus of elasticity for 7567 MPa,absorbing water thickness expansion rate for 5.48%,the inner combination strength of dry & wet state for 4.371 MPa/2.980 MPa,,the compressive strength for 84.06 MPa,which fully meet the best performance designed in the experiment.