| 摘要 |
<p>The profiled composite beam section, for building constructions, is built up from three separate extruded sections. A central straight link I-section (1) has re-entrant dove-tails at the ends (5). The upper beam (2) has a flat top and end flanges including a rectangular slotted portion suitable for door or window frames, an internal flange and a trapezium section rib (4) which fits tightly into the dove-tail cut-out (5) of the cross-link. The lower beam (3) is a simple flat member with short flanges and has a dove-tail fitting (4) similar to that of the upper beam. When fully assembled the dove-tail joints are weather proof.</p> |
