| |
|
How
to assemble:
A suspension-type structure
Pole
layout:
- Use
poles of 10.49 ft (3.2m), planted to a minimum depth of 23.62 inches
(600mm).
- Plant
two rows of poles 164.04 ft (50m) apart.
- Each
row consists of 18 poles at center-to-center intervals of 9.84 ft (3m).
- Prepare
19.68 x 19.68 ft (6x6m) poles by fitting 0.47 inches (12mm) drawbolts
through drilled holes at what will be 16.40 ft (5m) and 8.20 ft (2.5m)
respectively above ground level.
- Plant
these poles - three on each side of the square area - to a minimum depth
of 3.28 ft (1m) and at center-to-center intervals of 41.01 ft (12.5m).
- Brace
and anchor these 19.68 ft (6m) poles very securely with two stays each,
tied around the pole just above each of the drawbolts.
- Now
strain 0.19 inches (5mm) wire rope between the drawbolts at the 8.20
ft (2.5m) level and, preferably, more substantial 0.23 inches (6mm)
wire rope between the drawbolts at the top 16.40 ft (5m) level.
- Brace
and anchor the two rows of shorter poles by straining a wire along the
length of each row, across the tops of the poles. Alternatively, you
can nail split poles across the tops.
Fitting the shadecloth:
- Lace
up the shadecloth with edge wire as described previously and lift each
roll into position on the cross wire above the short poles.
- Secure
the edge wires and sew the cloth at one end and then roll the cloth
out over the lower cross wires between the tall poles.
- Fasten
and tension the edge wires, stretch the shadecloth and sew the opposite
end as described for other structures.
- Tie
binding wire to the upper cross cables, allowing it to hang down on
either side of the lower cross cables through the gaps between the shadecloth
sheets.
- Clip
or tie the edge wires together at approximately 19.68 inches (500mm)
intervals.
Lifting and stabilizing
the roof:
- To
achieve the desired"domed" effect, start at the midpoint of
the structure by lifting the center of the roof with the vertical tensioning
wires and tying the roof in position, as shown in the illustration.
- Then
lift the centers of the roof on either side with the other two pairs
of cross cables.
- Now
revert to the middle cross cables and tighten the tensioning wires to
the left and to the right of the center wire.
- Next,
tighten the corresponding tensioning wires on the two outer cable pairs,
and repeat the entire procedure until you reach the sides of the shadehouse
and all the tensioning wires are taut.
- The
upwards deflection of the roof stabilizes it against upward wind forces
whilst the tension in the top lifting cable stabilizes it against downward
wind forces.
- As
a general rule when erecting suspension-type structures larger or smaller
than the one illustrated, you can work to the distance between the top
and bottom lifting cables being 5% of the width of the span - in the
illustration, the span is 167.32 ft (51m), and the distance between
the upper and lower cables 8.20 ft (2.5m) (=5% approx.).
-
Ideally, all four sides should be enclosed as described earlier.
Other
building projects:
|
|
