Student ID : 10.01.03.080.
Course No : CE-416.
Course Title: Pre-stressed Concrete Lab
What is indeterminate structure?
The structure which can not be analysed by
the equations of static equilibriums alone are
called indeterminate structures.
This kind of structure consist of more
members and more restraints.
I. Moment distribution method
II. Slope deflection method
III. Matrix method- Stiffness method
- Flexibility method
IV. Column Analogy Method
V. The Method of Consistent Deformation
VI. Energy Method
Why Stiffness Method should use
The ability to automate the solution process.
Implementation in a computer program is
• Stiffness method is used for solving
problems related with,
• Stiffness Method:
The stiffness method is defined as the end
moment required to produce a unit rotation at
one end of the member while the other end is
• Degree Of Freedom (DOF):
Number of directions that the joints can
Degree of freedom for different
• Degree of Kinematic Indeterminacy (DOKI):
Total number of degree of freedom of the
i.e. degree of freedom at all the joints less
than no of restraints at supports.
DOKI=(Number of joints)*(Number of
DOF/joints)-Number of restraints.
The steps to be followed in performing
a stiffness analysis can be summarized as:
I. Determine degree of kinematic
II. Apply restraints and make it kinematically
III. Apply loads on the fully restraint structure
and calculate forces.
IV. Apply unknown displacement to the
structure one at a time keeping all other
displacements zero and calculate forces
corresponding to each degree of freedom.
V. Equilibrium equations are written and solved
in matrix form and obtain the value of
VI. All the member-end forces are calculated.