In post‑tensioning tendons routed through curvature zones, why do friction‑and-wobble losses materially reduce jacking forces recorded at stressing ends?

Choices

• (A) Curvature increases cumulative friction between tendon and duct
• (B) Stress stays perfectly uniform along tendon regardless of bends
• (C) Elastic shortening erases curvature effects
• (D) Curvature induces magnetic drag unrelated to ducts