IS 2062 fixes minimum yield strength (the E-number — note it reduces for thicker sections), ultimate tensile strength, and minimum percentage elongation (ductility), tested per IS 1608. The IS 800 design uses the specified minimum yield; the elongation guarantees the ductility that plastic design and robustness rely on. Yield is thickness-dependent — thick plate has a lower guaranteed yield than thin.
Key Requirements
•Minimum yield strength per the grade — note it DECREASES with increasing thickness (use the thickness-appropriate value)
•Minimum ultimate tensile strength and minimum % elongation (ductility)
•Tested by tensile test per IS 1608 Part 1 on a representative sample
•IS 800 design uses the specified minimum yield for the actual thickness — not the nominal E-number blindly
•Acceptance is strength AND ductility (elongation) together
Practical Notes
✓Yield is thickness-dependent — a 40 mm plate of 'E250' has a lower guaranteed yield than a 12 mm plate; using the nominal value for thick sections over-estimates capacity.
✓Elongation (ductility) matters for plastic design, robustness and seismic behaviour — not just the yield number.
Common Mistakes
⚠Using the nominal E-number yield for thick sections (ignoring the thickness reduction).
⚠Accepting on yield alone, ignoring elongation/ductility.