Figure 7: Stabilization of Tension: Minimum of 12 Spokes
solid mast without stays stands erect by itself in "solid" earth.
Tension stays may be added at end of the lever arm helping against
hurricane "overturning." Humans have until now employed a compression
continuity as the primary load-carrying structural system with tension
employed secondarily to stabilize angular relationships.
The old artillery wheel provides a series of compressional vaulting poles.
Pole vaulting along, a "pushing-up" load.
Hanging in tension like the wire wheel.
The wire wheel provides a series of tension slings. The axle
load of the wire wheel is hung from the top of the wheel, which
tries to belly out, so spokes as additional tension members are
added horizontally to keep it from bellying.
It takes a minimum of 12 spokes to fix the hub position in
relation to the rim: six positive diaphragm and six negative
diaphragm, of which respectively three each positively and
negatively oppose hub torque.
Many spokes keep rim from bending outwardly any further. The hub
load is suspended by central vertical spokes successively leading
crisscross from top of wheel tangentially to fore-and-aft sides
of hub and its load.
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Copyright 1999, Estate of Buckminster Fuller, all rights reserved.