Stressed membrane structure

A beam intended for a building structure, said building structure comprising a plurality of arc frame members and elongate membranes, said arc frame members spaced along a length of the building structure, each of said arc frame members comprising a plurality of beams which include said beam, each of said membranes secured by its opposite longitudinal edges between an adjacent pair of said frame members in a region between the interior and exterior of the building structure, said beam comprising:

• a central web extending between opposed first and second flanges, each of said flanges having two bifurcated ends, said ends defining c-shaped rope chases with openings;
• means for attaching, to said central web, a spreader extending from a beam of an adjacent arc frame member for urging apart the arc frame member containing the beam from the adjacent arc frame member and for maintaining said membranes in a stretched condition;
• said chases adapted for receiving said longitudinal edges,
• the rope chase openings of said first and second flanges being substantially angled out of the line of each flange toward the interior of the building structure in a manner so as to permit drawing said membranes through said rope chases with reduced friction during structure erection.

A telescoping spreader for moving apart spaced, adjacent arc frame members of a building structure, the spreader comprising:

• a substantially hollow bar defining a longitudinal axis of the spreader;
• a connector comprising first and second webs in substantially mutual perpendicular relation, the first web of which is adapted to be attached to a central web of an adjacent arc frame member in parallel relation therewith;
• an extension bar having a web adapted to be attached to said second web of said connector in parallel relation therewith, said extension bar extending along said longitudinal axis while attached to said connected, said web of said extension bar being separate from and intermediate opposed flanges of the adjacent arc frame member;
• said hollow bar for surrounding said extension bar, said hollow bar having interior ridges defining two opposed grooves therewithin adapted to accept said web of said extension bar in a sliding fit along a plane substantially longitudinally bisecting said hollow bar;
• and
• a locking assembly for fixing the position of said extension bar relative to said hollow bar.

A building structure comprising:

• a plurality of arc frame members spaced along a length of the building structure, each of said arc frame members extending from a first foot portion to a peak, and back to a second foot portion, each of said arc frame members comprising a plurality of beams, each of said beams comprising a central web extending between two opposed flanges, each of said flanges having two bifurcated ends, said ends defining c-shaped rope chases with openings;
• bases adapted to be slidably mated with said first and second foot portions;
• elongate membranes having beaded longitudinal edges, said membranes stretched between adjacent ones of said arc frame members, said longitudinal edges adapted to lie within said rope chases;
• and
• a plurality of spreaders each adapted to extend between adjacent ones of said arc frame members for urging apart said arc frame members from each other and for maintaining said membranes in a stretched condition,
• wherein each of said spreaders comprises a substantially hollow bar defining a longitudinal axis of the spreader, a connector, an extension bar, and a locking assembly,
• said connector comprising first and second webs in substantially mutual perpendicular relation, the first web of which is adapted to be attached to said central web of an adjacent arc frame member in parallel relation therewith;
• said extension bar having a web adapted to be attached to said second web of said connector in parallel relation therewith, said extension bar extending along said longitudinal axis while attached to said connector, said web of said extension bar being separate from and intermediate the opposed flanges of the adjacent arc frame member;
• said hollow bar for surrounding said extension bar, said hollow bar having interior ridges defining two opposed grooves therewithin adapted to accept said web of said extension bar in a sliding fit along a plane substantially longitudinally bisecting said hollow bar;
• and
• said locking assembly for fixing the position of said extension bar relative to said hollow bar.