Question

Number of unknowns to be determined in the stiffness method is equal to ............

• A. static indeterminacy
• B. kinematic indeterminacy
• C. sum of static and kinematic indeterminacy
• D. product of static indeterminacy and kinematic indeterminacy

Hint:

In the stiffness method, the unknowns are primarily the displacements (degrees of freedom), which relate directly to the kinematic indeterminacy of the structure.

Answer 1

The Correct Option is B

In the stiffness method of structural analysis, the number of unknowns to be determined is equal to the kinematic indeterminacy. This is because the method primarily focuses on determining displacements (degrees of freedom) as unknowns, which are associated with the kinematic indeterminacy of the structure.
- Static indeterminacy refers to the number of reactions or forces that cannot be determined using only the equilibrium equations.
- Kinematic indeterminacy refers to the number of independent displacements (such as rotations and translations) that cannot be determined directly from the geometry of the structure.
Thus, the stiffness method is concerned with resolving the kinematic indeterminacy of the system.