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If in a rigid-jointed space frame, (6m + r) < 6j, then the frame is
- AUnstable
- BStable and statistically determinate
- CStable and statistically indeterminate
- DNone of the above
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CCommunity
The degree of static indeterminacy of a rigid-jointed space frame is
Ds = (6m + r) - 6j
Where, m = number of members in the joint, r = number of equilibrium equations and j = number of joints
When,
Ds = 0, then the truss is stable and determine, such trusses is called perfect trusses.
Ds > 0, then the truss is stable but indeterminate or over stiff
Ds < 0, then the truss is unstable or deficient.
Hence, Ds = (6m + r) - 6j < 0, the truss is unstable.
Ds = (6m + r) - 6j
Where, m = number of members in the joint, r = number of equilibrium equations and j = number of joints
When,
Ds = 0, then the truss is stable and determine, such trusses is called perfect trusses.
Ds > 0, then the truss is stable but indeterminate or over stiff
Ds < 0, then the truss is unstable or deficient.
Hence, Ds = (6m + r) - 6j < 0, the truss is unstable.