Extruded hollow girder with reinforcement insert - has steel strips in slots inside beam in regions of high tensile stress

摘要

The girder (13) is made of material of low tensile strength and regions of high tensile stress are reinforced (35) with high tensile strength strips secured to the ends of the girder. The girder may be of extruded plastics or aluminium alloy while the reinforcement is steel. The reinforcement may be inserted in a hollow slot of the girder section, e.G. a girder of rectangular box section may have undercut recesses parallel to one of the narrow sides to support a flat strip reinforcement. The strip may be secured to the ends of the girder by screws.