SSC JE Civil Engineering 30-Oct-2020 Shift 2 Paper

Concept:Kinematic Indeterminacy:It is the total number of possible degrees of freedom of all the joints.
${\mathrm{D}}_{\mathrm{k}}$ = 3J - r + h (For beam & portal frame)
${\mathrm{D}}_{\mathrm{k}}$ = 2J - r + h (For truss structure)
Where,
${\mathrm{D}}_{\mathrm{k}}$ = Kinematic Indeterminacy,
r = No. of unknown reactions
h = No. of plastic hinges
J = No. of joints
Calculation:Given;
J = 2
R = 1 + 3 = 4 (1 vertical reaction at roller support, and 1 vertical, 1 horizontal and 1 moment reaction at fixed support)
h = 0
${\mathrm{D}}_{\mathrm{k}}$ = 3 × 2 - 4 = 2
${\mathrm{D}}_{\mathrm{k}}$ = 2