Structural Steel — Worked Examples

A machined steel coupon has original cross-sectional area $A_0=200\text{ mm}^2$. The load at a reported yield point is $70.0\text{ kN}$. Determine engineering yield stress.

The same coupon reaches a maximum load of $100\text{ kN}$. Its original gauge length is $50.0\text{ mm}$ and final gauge length after fracture is $62.0\text{ mm}$. Determine ultimate engineering stress and percent elongation.

A beam arrives with heat number H7421 stamped on its identification tag. The submitted mill test report lists heat H7241. All reported strengths on the certificate meet the specified grade. Decide whether the shipment is traceable.

A project specification requires impact testing for a particular steel component at a stated test temperature. Three specimens from the required set produce 34 J, 31 J, and 36 J. Explain the correct evaluation approach without inventing an acceptance threshold.

A welded steel fabrication has a suspected surface-breaking crack near a weld toe and a separate concern about an internal lack-of-fusion indication. Select suitable nondestructive examination families.

Five coating-thickness readings on a steel member are 245, 260, 252, 248, and 255 micrometres. Calculate the mean thickness and explain the limitation of the average.

A stainless-steel fastener is proposed in direct contact with a carbon-steel plate in a wet chloride environment. Determine what should be evaluated before installation.

A thick welded plate component develops a sudden crack during cold-weather service. Mill certificates show the specified yield and tensile strengths were achieved. Determine why strength compliance alone is insufficient.