Fig. 8
From: Balanced Ratio of Concrete Beams Internally Prestressed with Unbonded CFRP Tendons
Comparisons of Δf ps : test results and predictions by three equivalent curvature block model versus predictions by Eqs. (14) or (15) (30 MPa ≤ \( f_{c}^{'} \) ≤ 50 MPa, 0.4 ≤ f pfi /f pfm ≤ 0.6, 525 mm ≤ d pf ≤ 575 mm 1.0 ≤ A bf /A bf,min ≤ 2.0, 0 ≤ L p /L ≤ 0.5, 1.0 ≤ ρ U pf /ρ B pfb ≤ 1.2). a Equation (14) for beams with auxiliary bonded steel bars. b Equation (14) for beams with auxiliary CFRP bars. c Equation (15) for beams with auxiliary bonded steel bars. d Equation (15) for beams with auxiliary CFRP bars.