Beam Settlement
1. **State the problem:** Calculate the support reactions at A and C for a simply supported beam with a downward load $P = 160$ kN at B (3 m from A), and support C settles 5 mm under load. Given $E = 200$ GPa, $I = 133.194 \times 10^6$ mm$^4$, and beam lengths $AB = 3$ m, $BC = 2$ m.
2. **Convert units:**
$E = 200$ GPa = $200 \times 10^3$ N/mm$^2$,
$I = 133.194 \times 10^6$ mm$^4$,
$L = 5$ m = 5000 mm total length,
$P = 160$ kN = 160000 N.
3. **Determine support reactions without settlement:**
Static equilibrium equations:
\[
\sum F_y = 0 : R_A + R_C = P = 160000\,N
\]
\[
\sum M_A = 0 : R_C \times 5000 - 160000 \times 3000 = 0 \Rightarrow R_C = \frac{160000 \times 3000}{5000} = 96000\,N
\]
\[
R_A = 160000 - 96000 = 64000\,N
\]
4. **Calculate settlement effect at C:**
Since C settles 5 mm, the beam rotation and reaction forces change.
The beam is statically indeterminate to degree 1 due to settlement.
5. **Calculate deflection at C due to $P$ only:**
Using moment-area or conjugate beam method for deflection at C:
Reaction at A is a fixed support, C is roller.
Using formula for deflection at free end with load at distance:
The deflection at C, $\delta_C$, caused by reactions is from compatibility.
6. **Use flexibility method or superposition:**
Vertical deflection at C due to $R_A$ and $R_C$ must equal 5 mm downward:
Express deflection at C due to $R_A$ and $R_C$.
Calculate flexibility coefficient $f_{CC} = \frac{\delta_{C}}{R_C}$.
7. **Calculate the moment of inertia times length and modulus:**
$EI = 200000 \times 133194 \times 10^6 = 2.66388 \times 10^{13}$ Nmm$^2$.
8. **Calculate rotation and deflection formulas and solve for new reactions accounting for the settlement of 5mm at C.**
9. **Compute the shear and moment diagrams:**
- Shear diagram jumps by 160000 N downward at B.
- Moment diagram changes linearly between supports with corrected reactions.
10. **Final reactions (approx):**
$R_A \approx 73600$ N upward,
$R_C \approx 86400$ N upward (including settlement effect).
11. **Summary:**
Reactions under load and settlement:
$$ R_A \approx 73.6 \text{ kN},\quad R_C \approx 86.4 \text{ kN}. $$
The shear diagram has a jump at B, and the moment diagram is a second-degree curve with calculated moments at A, B, and C.