If in a rigid-jointed space frame, (6m + r)

Question

If in a rigid-jointed space frame, (6m + r) < 6j, then the frame is
A)unstable
B)stable and statically determinate
C)stable and statically indeterminate
D)none of the above

Quizplus · Accepted Answer

For a rigid-jointed space frame to be stable and statically determinate, the equation (6m + r) = 6j must hold, where m is the number of members, r is the number of reactions, and j is the number of joints. If (6m + r) < 6j, it means there are not enough members and reactions to prevent movement, making the frame unstable.

If in a Rigid-Jointed Space Frame, (6m + R)