Disclosed is a composite beam structure having: an end piece, an end piece outer periphery surface, and an end piece mating end defining an end piece axial boundary, the end piece includes wedge-shaped inner locking features that are formed to project outwardly from the end piece outer periphery surface at the end piece mating end and are spaced apart from one another in the hoop direction; and a composite tube configured to surround at least a portion of the end piece mating end to form a beam joint, wedge-shaped imprints are formed through the composite tube, corresponding to the wedge-shaped inner locking features, the wedge-shaped imprints define respective composite tube wedge-shaped depression surfaces about a composite tube inner periphery and composite tube wedge-shaped boss surfaces about a composite tube outer periphery, and the wedge-shaped inner locking features of the end piece are covered by the composite tube wedge-shaped depression surfaces.