Section bar assembly

The utility model relates to a sectional material assembly which comprises a sectional material and a core material, and a cavity is formed in the sectional material. The composite material is characterized in that the core material comprises a first core material body and a second core material body with the density smaller than that of the first core material body, the first core material body and the second core material body are both contained in the cavity, the filling proportion of the first core material body in the cavity is 20%-70%, and the filling proportion of the second core material in the cavity is 20%-50%. The utility model further relates to application of the sectional material assembly. The core material disclosed by the utility model has better flame retardancy, the first core material with larger density is high in mechanical strength and can support the inner wall of the cavity, the structural stability of the sectional material assembly when burning with fire is ensured, and the second c