Diffrence Between Flexibility Matrix And Stiffness Matrix

FLEXIBILITY METHOD

STIFFNESS MATRIX METHOD

This Method is also referred as force or comp ability method.

This Method is also called as Displacement method.
Primary Unknowns are redundant Forces.
Primary Unknowns are Joint displacement.
Primary Unknowns can find out by structures comp ability equation.
Primary Unknowns are finding out by Solving Structures equation of equilibrium.
Flexibility Method deals with Structural Static indeterminacy of structure.
Stiffness Method deals with kinematic indeterminacy of structure.
In Flexibility Method Primary Unknown forces are like Bending Moment, Shear Force, Axial Force etc.
In Stiffness Method Primary Unknowns are Vertical- Horizontal Displacement and Rotation at joint.
As Name implies this method is Flexible to choose Unknowns.
Stiffness Method Has No such Choice.
Bending Moment and Shear Force values of result analysis are taken so that the stress values obtained is limited to permissible value.
By knowing displacement and rotation. To meet Serviceability criteria and checking rotation capacity makes it more Practical.
This method is in The form of classical Method of consistent deformation.
This Method uses Slop-Deflection Equation.

This method is more convenient For analyzing small structures with few redundant.

This Method is more Preferred for analysis of Large and Highly Redundant structure.
This Method is Hard and Critical to program in computer software’s hence it is not used in professional Practice.
This Method is Easy to program in computer software’s and hence it is widely used in professional practice.

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