The construction details of the tensile structures are as follows:
Seams and joints: both workshop seams (stitched and welded) and on-site seams (glued, corded, bonded and welded). The seams are characterized by transmitting the loads that circulate through the fibers. These require fabric perforation, seam sealing and thread protection. Currently the trend is to make the roofs in one piece, however, it is common that joints are needed on site to join the different parts by means of stringcourses, bolted, welded or glued handrails.
Perimeter edges: their stiffness influences the tensional state and shape of the membrane. Edges can be flexible (unreinforced, reinforced with hem, tape, cord, inner cable or outer cable), semi-free (with transition elements) and rigid (tube, profile, channel, guide). The flexible edges deform, thereby relaxing stresses and increasing curvature. Rigid edges, on the other hand, deform very little, so they do not produce the damping effect of stress peaks due, for example, to a gust of wind or accumulated snow. There are several procedures to continuously resolve the connection of the membrane edge with a rigid structural element, such as using a tube or profile. The edge can be pressed and screwed so that the tension is transmitted from the membrane to the perimeter bead, from the bead to the clip, from the clip to the screws and from the screws to the handrail, plate, gusset or profile.
Edges: hanging files, supported files, cable-stayed files and supported files.
Corners: outside or open and overlapping or closed.
High and low points: the charges circulating on the membrane surface are concentrated until they reach the junction point. As the stress would easily exceed the admissible value, it is necessary to widen the point, which becomes a circle of larger or smaller diameter, and to reinforce the membrane. The stress to be transmitted divided by the allowable membrane tension and by the number of layers gives the value of the required perimeter.
– Anchor plates: these are the bases of masts and anchorages and are usually hinged to facilitate assembly. There are particular cases in which it is of interest that they are embedded. Anchors can be active (prestressed) and passive surface anchors (stakes, piles, shafts, footings, screen elements, sheet piles, massifs, bags, pipes) or deep anchors (plates, propellers, profiles, gratings, logs, bars or massifs).