Introduction to Tensile Fabric Structure Design Concept
One of the most flexible free-form building are fabric structures. Its lightweight characteristic offers immense variety of building application & design. Tensile fabric structure is a type of tensile membrane structure. Membrane structures can be free form structures and are dependent on curvatures to distribute load evenly in tensioned stat.
Some common roof system failures are inability to withstand or carry load such as amount of wind, rain and snow. Removing deflection from wind, rain and snow from roofs is more dangerous than efficient. Hence, fabric structures were developed to have double curves on tensioned membrane structures to carry the weight or load of the wind, snow and rainfall.
There are several basic forms and types of tensioned membrane structures. Namely anticlastic and synclastic structure. Anticlastic is pure tensioned structure that can be seen in most cone, sail and arch design. Synclastic is air supported structure with air in between create a pillow like structure.
(1)Anticlastic structure -Tensioned Membrane Structure
a) Hypar Sail Design
Paraboloids have surface divided in quadrants. Hyperbolic paraboloid looks like a saddle where the surface has high and low points. It is a form of anticlastic tensioned membrane. In the design of fabric structures, a hypar or saddle shape offers stability. Hypars normally have two high and two low points opposing each other. These points resists wind flow that lifts the fabric.
b) Cone Design
Another type of anticlastic are the cone and arch forms. These are popular and mostly used in canopies and other roof membranes. The cone can also be an inverted conical.
c) Arch Design
The most common type of fabric roof is the arch-shaped fabric structure. Arch shapes generate by bending the steel frame profile in order for the membrane fabric to wrap around to form a barrel vault structure.
(2) Synclastic Structure – Inflatable or Air Dome Shape
A type of synclastic structure is the inflatable or dome-shaped forms. Constant pressure of air helps to give the fabric its balloon shape which shows double curvature as well. It is normally installed over sports-complex, gardens and etc where large span is required.
Tensioned fabric structure is commonly built with a combination of two or three forms and shapes. Building it from a modular unit to form more complex combination solution in tensile fabric design.
Tensile fabric architecture is the design of fabric material roofing that form freely with the minimum support structure where tension is applied. All materials used in the installation of fabric structures are all subjected to details design & engineering in tensile fabric structure.
Architects/designers and engineers find various challenges when it comes to developing new styles and forms to better suit the need of roofing systems. Each design should address pre-stress conditions to ensure the integrity and stability of the fabric structure. Equal distribution of fabric load over each membrane is the key to a perfect and reliable roofing system.
TE Membrane is Tensile Fabric Structure Specialist.