Tensegrity Structures: Stabilization through tension

Tensegrity engineering and architectural design utilizes a combination of isolated components, usually bars or struts contained inside a continuous net of precisely compressed cables or tendons.  When the design is successful, the individual bars never touch one another, and the structure remains perfectly balanced through the application of continuous tension from the prestressed cabling members.    Also referred to as tensional integrity or floating compression engineering, the structure will only fail if the rods buckle or the tension wires fail.

Standard applications of tensegrity structures include bridges, domes, towers, stadium roofing systems, and other oddly shaped architectural features.  Examples include the 60-foot Needle Tower sculpture at the Hirshhorn Museum and Sculpture Garden in Washington, D.C., the Estadio Ciudad de La Plata in Buenos Aires, and the Munich Olympic Stadium in Germany.  Meanwhile, Brisbane, Australia is home to Kurilpa Bridge, the world’s most-expansive tensegrity bridge.

Benefits of tensegrity structures

A unique characteristic of tensegrity structures is that they are extremely responsive to outside applied forces.  When an applied force occurs to an individual element, the entire structure reorients and adapts automatically without jeopardizing its structural integrity.  Because each cable component is prestressed, they apply perfectly-balanced pressure to both ends of the bars or struts which keeps the entire structure in place.  Other benefits include the following.

• Increased efficiency and deployment:  An attractive benefit of tensegrity structures is that portions can be pre-fabricated off-site.  This enhanced portability means that engineers can have areas pre-assembled in a factory before being transported to the construction site by truck or helicopter for installation and more efficient deployment.   
• Easily adjustable:  Tensegrity structures can be quickly and easily “fine-tuned” when individual components become damaged in some regard.  By simply readjusting the applied tensile strengths in the affected design elements, the structure remains fully intact.
• Structural equilibrium:  Because the individual elements are so intimately interconnected and interdependent upon one another, the applied forces to one component are essentially transmitted throughout the entire structure.  The cables pull on the ends of the struts, and the struts stretch or elongate the cables, keeping the entire design is a state of prestressed, pre-compressed structural equilibrium.

Advancements in engineering are leading to an increased demand in construction projects with a need for both static and active design elements.  With tensegrity structures, an individual component can serve multiple functions.  For example, in addition to offering load-carrying properties, an individual element can also act as a sensor, actuator, thermal insulator, or electrical conductor simultaneously.  Tensegrity design can also provide other significant benefits for structures under constantly changing demands of load variations and temperature fluctuations, which is yet another reason that tensegrity engineering is gaining such worldwide popularity.