Table 3 Minimum effective prestress (fse,min) to satisfy the tensile stress limit (Δfps,allow).
From: Control of Tensile Stress in Prestressed Concrete Members Under Service Loads
Section shapes | PPR 100% (∆f ps ≤ 250 MPa) | Partially prestressed concrete members (PPR ≥ 50%) | ||
|---|---|---|---|---|
f y = 420 MPa (for ∆f ps ≤ 250 MPa) | f y = 550 MPa (for ∆f ps ≤ 250 MPa) | f y = 550 MPa (for ∆f ps ≤ 350 MPa) | ||
R | 0.50 f pu | 0.50 f pu | 0.55 f pu | 0.50 f pu |
T | 0.50 f pu | 0.50 f pu | 0.60 f pu | 0.50 f pu |
IT | 0.50 f pu | 0.50 f pu | 0.50 f pu | 0.50 f pu |