PURPOSE: To enable the maintenance of constant energy absorption by establishing the ratio of the dimension of the first pipe on a press-fitting side to the dimension of the second pipe to be within the range of 1:1.1-1:1.3, and the angle of inclination of an oblique pipe-shaped pipe to be more than 30°.

CONSTITUTION: Slit-shaped notches 5 formed at the one end of a FRP pipe 4 composed of a glass fiber impregnated with thermosetting resin makes the inclined part of an oblique pipe-shaped pipe 3 enter the periphery of the tip of the FRP pipe when a load acts in the axial direction of the FRP pipe 4, and the periphery at the tip of the FRP pipe is thereby expanded to absorb energy for producing excellent absorbing characteristics. Since the pipe 4 is made of fiber reinforced plastics, its initial elasticity is high from the first stage of the characteristics of energy absorption till a fixed load is charged onto the pipe 4. In the case where the ratio of B/A(A and B are denoted in the figure.) is within 1:1.1-1:1.3, and the angle C of inclination of the oblique pipe-shaped pipe 3 is more than 30°, energy absorption load is about constant to positional variation, and in the case where the ratio of B/A is above 1:1.4, or the angle of inclination is below 30°, the characteristics of load is not constant to the positional variation.