Steel Tensile Strength Testing: Ensuring Structural Integrity

Key Properties Measured

Tensile testing provides essential mechanical properties for structural calculations:

• Yield Strength (ReH or Rp0.2): Stress at which permanent deformation begins
• Ultimate Tensile Strength (Rm): Maximum stress the material can withstand
• Elongation (A): Measure of ductility expressed as percentage increase in length at fracture
• Modulus of Elasticity: Stress-strain relationship in elastic range
• Reduction of Area: Measure of ductility from cross-section change at fracture point

Testing Standards and Procedures

Steel specimens are machined to standard dimensions and tested in a universal testing machine. Load is applied at a controlled rate while measuring elongation with extensometers. Testing follows EN 10002-1, ASTM A370, or equivalent standards. For reinforcing bars, full-size specimens are typically tested. For structural sections, machined specimens are extracted.

Steel Grade Verification

Results must meet minimum requirements for the specified grade. For example, S355 structural steel must achieve minimum yield strength of 355 MPa and ultimate strength of 470-630 MPa. B500B reinforcement must achieve minimum yield of 500 MPa and elongation of 5%. Mill certificates are verified against actual test results.

Common Applications

Tensile testing is required for structural steel, reinforcing bars, prestressing strands, metal plates, bolts, and weld samples. It's performed during material qualification, factory production control, and on-site verification. Critical structures like bridges, high-rises, and nuclear facilities require extensive testing programs.