Load Analysis - Tensile Fabric Structures: Design, Analysis, and Construction - page 95

Solve for:
δ = PL 3 /48EI = 18 mm (6.2-1)

Next, consider the cable in Figure 6-2 tied between two supports. When load is
applied, the cable will grow taut and deflect. A small load will result in a relatively
large deflection. The deflection will not be linearly proportional to the applied load.
The vertical resistance of the cable is dependent on the cable tension and deflection.
Solution strategies for solving this non-linear geometric problem are considered in
Chapter 5. Verifying that the correct solution has been identified can be done with
linear analysis.

Figure 6-2
Cable
(Drawing by the author)

Given:

P = 10.0 kN (applied vertical load)
L = 6000 mm
A = 40 mm 2
E = 200 kN/mm 2

T PRESTRESS = 0.0 kN

Check:

δ V = 325 mm (calculated vertical cable deflection)

Find:

T = Cable tension
T V = Vertical component of cable tension
L=

3000  = 3017.6 mm
δ L = 3017.6-3000.0 = 17.6 mm
T= δ L AE/L = 46.81 kN

2 2

325

(6.2-2)

T V = 46.81*(325/3000) = 5.07 kN

Next, consider the prestressed cable in Figure 6-3 anchored to the same two supports.
As in the previous example, the vertical resistance of the cable is dependent on the
cable tension and deflection. Prestressing the cable will result in increased cable
tension and decreased deflection. Again, verifying that the correct solution has been
identified can be done with linear analysis.