Preparation method of lightweight composite material and lightweight high-sound-insulation composite material

The invention provides a preparation method of a light-weight composite material and a light-weight high-sound-insulation composite material, according to the method, reinforcing ribs which are staggered transversely and longitudinally are added in a sandwich material of the composite material, the density of a core material is reduced, so that the light weight of the composite material is achieved, and the method is simple to operate and easy to implement; the thickness of the sandwich can be better controlled when the long strips II are spliced into the sandwich through bonding and cutting. By adding the transverse and longitudinal reinforcing ribs, the excellent mechanical property of the product can be realized, the density of the foaming material is reduced, and the weight of each part of the rail transit can be reduced by more than 20%. The invention further provides a light-weight high-sound-insulation composite material, the sandwich material is used, good mechanical performance and light weight are g