Domains of deformation

Conventional failure due to excessive plastic deformation:

• — line a: uniform tension;
• — domain 1: non-uniform tension, without compression;
• — domain 2: simple or composite bending without failure due to concrete compression (ε_c < ε_cu and with the maximum allowed elongation).

Conventional failure due to concrete shortening limit:

• — domain 3: simple bending (under-reinforced section) or composite with failure due to concrete compression and steel yielding (ε_s ≥ ε_yd);
• — domain 4: simple bending (over-reinforced section) or composite with failure due to concrete compression and tensioned steel without yielding (ε_s < ε_yd);
• — domain 4a: composite bending with compressed reinforcements;
• — domain 5: non-uniform compression, without tension;
• — line b: uniform compression.

Compression Stress-Strain Diagram