How is creep in concrete predicted and accounted for in structural design?

Creep (time-dependent strain under sustained stress) is predicted using models like ACI 209, CEB-FIP, or Eurocode 2 formulations. Key factors include: loading age, relative humidity, volume-surface ratio, concrete strength, and loading duration. Creep coefficient (ratio of creep to elastic strain) typically ranges 1.5-3.0. In design, creep causes increased deflection in beams (multiplied by factor 1+creep coefficient), stress redistribution in columns, losses in prestressed concrete, and long-term deformations in tall buildings affecting facade systems.