Degree of Static Indeterminancy.
Ds = R-E = 4-3 = 1
Assuming Ds = Number of redundant force R
Portion | Origin | Limit | Mxx | M1 |
DC | D | 0-2 | 0 | 0 |
BC | C | 0-4 | -10X²/2 = -5X² | +X |
BA | B | 0-5 | -20X – 1042 = -20X-80 | 4 |
Actual displacement at redundant = 0
[ D ] = [ ΔL1 ] + δ11 * R1
0 = – 2920 / EI + 101.33 / EI * R1
R1 = 2920 / 101.33 = 28.21 KN