To obtain a more lightweight beam member with higher flexural rigidity than a conventional beam member by holding deflection in the application of a load to a low degree.
This beam member, which is manufactured of carbon fiber reinforced plastics, has any one of a solid structure, a hollow structure and a structure whose inside is filled with an expanded material. The beam member includes at least one layer wherein an overall-length/cross-sectional-thickness (height) ratio is in a range of ≥20 and ≤400, wherein a modulus of elasticity in tension of a carbon fiber is in a range of 200-900 GPa, and wherein and the oriented direction of the carbon fiber forms any one of angles of 0°, 90° and ±45° with the longitudinal direction of the beam member.
SAKAMOTO AKIO
SANOKAWA YUTAKA
