Deck Section Modulus

Deck section modulus Z_d = I / y_d - governs bending stress in compression at the deck for a sagging wave.

Structural

Hull-girder moment of inertiam⁴Distance neutral-axis to deckmDistance neutral-axis to keelm

Deck section modulus Z_d: 5.714m³

Keel section modulus Z_k: 7.059m³

Changing the inputs requires JavaScript. The calculator above shows its default inputs and result. The formula, symbols, and regulatory sources are shown in the Formula section below.

Formula, assumptions, and limits

Z_d = \frac{I}{y_d}, \quad Z_k = \frac{I}{y_k}

Symbol	Meaning	Unit
$I$	Hull-girder moment of inertia	m⁴
$y_d, y_k$	Distances from neutral-axis	m
$Z$	Section modulus at deck / keel	m³

Source: IACS CSR-H

In short

Deck section modulus Z_d = I / y_d - governs bending stress in compression at the deck for a sagging wave.

Learn the theory Hull Strength and Longitudinal Bending