Midship Section Modulus - Rule Minimum
Rule-minimum midship section modulus from total bending moment (SWBM + WBM) and the allowable stress per IACS UR S11.
Total BM
9,000,000kN·m
Minimum Z required
51.429m³
Formula, assumptions, and limits
σ_allow 175 N/mm² is the classical IACS UR S11 value for mild (Grade A) steel. Higher-tensile scantlings use 175/k with k = 0.78 (AH32), 0.72 (AH36), 0.68 (AH40), 0.62 (AH47).
Symbol legend
| Symbol | Meaning | Unit | Source |
|---|---|---|---|
| Still-water BM | kN·m | loading computer | |
| Wave BM | kN·m | IACS UR S11 | |
| Allowable nominal stress | N/mm² | IACS S11 |