Load Analysis - Tensile Fabric Structures: Design, Analysis, and Construction - page 94

Chapter 6
Load Analysis
6.1 Codes and Standards
Although the materials used in tensile membrane structures and their behaviors under
applied loads follow well established principles of mechanics, they are often outside
the realm typically considered for building structures. ASCE Standard 17-96, Air
Supported Structures , ASCE Standard 19-96, Structural Applications of Steel Cables
for Buildings and ASCE Standard 55-10, Tensile Membrane Structures contain useful
information relating to the design of tensile membrane structures. Behavior
characteristics which are critical to understanding and evaluating tensile membrane
structures under applied loads are considered in this chapter.
6.2 Non-linear Response to Applied Loads
Unlike structures with significant shear and flexural stiffness, the geometric changes
in the form of a tensile structure under applied loading are often significant and must
be included in the analysis. The influence of geometric deformation is generally non-
linear. Consequently, superposition of the results from various load cases is usually
not valid in the analysis of tensile membrane structures.
For example:
Consider the beam in Figure 6-1 spanning between two supports. When a load is
applied, the beam will bend as it transfers the vertical reactions of the load to the edge
supports. Analyzing the beam again using the original load and the calculated
deformed shape will generally not provide additional insight into the beam's
behavior.
Figure 6-1
Beam
(Drawing by the author)
Given:
P = 10.0 kN (applied vertical load)
L = 6000 mm
EI=2.5 x 10 9 kN*mm 2
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