architectural membrane association
To transfer the loads superimposed with the membranes pre-tension into the primary structure, the membrane ideally needs a double curvature. This double curvature is obtained by pulling the membrane out of the plane either up- or downwards. In case of a point-shaped membrane deflection in the center of the surface high and low point details are used - in the case of line-shaped area deflection so called ridge and valley details.
High and Low points can be considered as internal edges of a membrane surface. The form of these raised or lowered points are mostly circular rings where the membrane is attached to by bended clamping bars. Outer masts are supporting the rings or the ring is suspended from a primary structure above.
The circular ring is generally covered in order to create a watertight detail. In case of a low point application drainage needs to be considered at these points.
Linear deflection of membrane surfaces are generated by pushing cables from the top downwards into the surface or vice versa by pulling cables from underneath upwards. In both cases this cable is mainly integrated into a cable pocket, thus considered as an internal boundary edge of the membrane structures. The design principals of boundary cable pockets also apply for this application. The size of the cable pocket should allow to move in the cable easily. The cable pocket might be reinforced by a second layer.
It is advisable forseeing anchoring points at the corner plate for attaching devices to apply pre-tension into the membrane during installation. This can be a simple additional hole in the corner plate which allows the fixation of a ring screw for example where belts can be inserted for pulling the structure into final position.
It is important to round off all edges of the corner plate to avoid any injuries when handling the detail.