Engineering is critical to the success of any fabric tension structure and includes:
- Determining applicable loads, pre-stress, and final design strength and serviceability loads
- Determine reactions and subsequent structural behaviour
- Design Structure/Critical Detailing/Connection
- The whole process is iterative and requires simultaneous resolution of several issues of:
- Installation efficiency
This is somewhat counter-intuitive when compared to more traditional approaches to construction. A tensile structure requires that the method of fitting and tensioning the membrane be resolved at the same time as locating efficient connection points.
Furthermore, the final form of the membrane will have a significant influence on the loads, and changes in heights will impact form and reactions thereby influencing fittings/connections and structure.
Designers of tension membrane structures, regardless of the size or degree of simplicity or complexity, need to work together in partnership with engineering to enable these critical issues to be addressed satisfactorily to ensure the best outcome.
Proper engineering is paramount and fundamental to ensuring not only a safe and structurally sound product, but it is also essential in ensuring that the fabric is able to perform to its optimum design, maintain tension and rigidity under load, and maintain shape and form in service for the duration of its life.
The smaller and more accessible consulting engineers, normally familiar with ‘domestic or commercial’ building projects, are often called upon to undertake what may appear to be simple engineering designs for the smaller shade projects. Their approach might well be to apply ‘rigid type structure loading’ with little knowledge or appreciation of the unique behaviours of membrane structures. This is not a criticism of these engineers, but rather, it demonstrates that the ability and resources to undertake proper engineering is not at the fingertips of every engineer. The many failures of fabric structure we see today are testament to this.