The dimensions of the structure considered for the present simulation is shown in the cross

section in Figure C1. The height of the structure considered was 10 feet above the ground while

the total length in the case of the model was 11 feet. Also from the boundary condition point of

view the support condition was considered to be similar to that of a cantilever beam type. This

type of support condition has been considered for the initial simulations purposes only as it

represents the worst-case scenario. However, as can be seen in the installation procedure in

Figure C1 the actual boundary condition subjects far greater constraint on the structure than

achieved by this assumption. The table gives the material properties of the PVC considered for

the present case.

380,000 psi

Tensile Strength

6300 psi (<5% Total Strain)

Static linear elastic finite element analysis

of the structure was carried out using the

ANSYS FEM software. To model this

6.5"

structure for the purpose of the Finite Element

Analysis (FEA) the structure was simplified.

As shown in Figure C4 the web and flange

were modeled using the Elastic SHELL 63

2"

5"

5"

elements of thickness 0.25". The length of

structure as pointed out earlier was 11 feet.

The Rib and the corner stiffeners were

modeled using the Elastic BEAM 3 elements

of diameter 0.5", cross section area of 0.196 sq in and area moment of inertia of 0.0031 in4. Also

the connecting `C' joints were modeled as the beam element, which can be further, refined to

model the exact geometry of the structure.

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