Textile architecture and membranes
About the membrane
Hi-tech, technical construction, but working with a very fine and soft material - a fabric with almost organic shapes. The fineness and grace of the curves go hand in hand with the tension that we bring into the fabric. It is the result of centuries of research into shapes and materials, from the Romanesque arch, the Gothic vault, through beautifully shaped subtle concrete shells to the complete purity of the material and the shape of two curvatures - the fabric and the hyperbolic paraboloid. The cold hard construction brings out a fine, light and graceful textile.
What does the membrane structure consist of?
Generally, we divide membrane textile structures into two basic parts – the membrane and the structure.
Membrane elements
The membrane fabric is made of polyester (PES) fabric with a top multiple-lacquered layer with highly concentrated PVDF on both sides. The fabric is characterized by high tensile strength. To achieve the desired shape, it consists of individual cuts that are cut on a digital cutter. These are then welded using a high-frequency press. The fabric is resistant to external influences - it resists UV radiation, mold and fungi, and is easily washable.
The edges of the fabric deform when stretched, it is its nature to deform at the edge into an arc (more precisely, a catenary). In order for the fabric to hold the desired shape, we insert ropes into these arcs. The ropes are terminated at both ends in fittings on the membrane. The ropes, together with the fittings, define the membrane and help shape it.
The elements at the ends of the membranes are called fittings. They serve as a transition element between the membrane and the anchoring structure. In simple terms, if we want to pull or push the fabric somewhere, we use fittings. The fittings have a specific shape for each given case. The ropes, together with the fittings, border the membrane and help shape it.
The membrane must be anchored and tensioned (pre-tensioned). This is done using tensioning elements that hold the fabric to the structure and, after the fabric is stretched, fix it in the desired shape.
Construction elements
The membrane is anchored to the columns via a rectifying element. The columns are stressed by buckling, transferring the compressive component of the force from the membrane (alternatively also the bending pressure in the case of being embedded in the foot). In the best case, they are used in combination with an anchor rope and thus combine the advantages of both structural elements. It is appropriate to anchor the column to the foundation with a swing or ball joint, a less suitable solution is to embed it. The columns are often made of steel, but it is also possible to use wood.
The cable (alt. tie rod) transfers the tensile component of the prestressing force from the membrane to the foundations or anchor structure. When using anchor cables, the requirement for column dimensions is significantly reduced. The anchor cable is terminated with forks and often also allows for the rectification of the entire structure.