To raise a freedom degree of a shape by improving fire resistance, water-proofness, light weight properties, strength, and durability of a large-sized structure to make moldability excellent by a method wherein a layer comprising a reinforcing fiber and an inorganic matrix material is arranged on at least one surface of a core material having a groove extending continuously on the surface.
A reinforcing fiber base material 23 is arranged in a facial direction of a core material 22 in contact with the core material 22 wherein a groove is provided to at least its one side, after covering the whole with a back film 29, an inside covered with the back film 29 is evacuated, and inorganic matrix liquid is injected. That is, the core material 22 consisting of a foam is arranged in a mold 21, and the reinforcing fiber base material 23 are arranged on at least both sides thereof. Each core material 22 has a large groove being a passage of the matrix liquid as a continuous groove, and many small grooves branched from the large groove. The matrix liquid is impregnated into the base material 23 in a thickness direction while being diffused in the surface direction of the reinforcing fiber base material 23.
TERASHITA TAKESHI
ENDO ITARU
SEKIDO SHUNEI
