PSAD SITUATION 140: Prestressed Hollow Core Slab | CELE May 2017

CELE Past Board Exam Problem To learn more, enrol now to iReview Tutorial and Review Center: https://www.facebook.com/share/1AC24W... SITUATION: Prestressed hollow core slabs with typical section shown in the figure are used for the flooring of a library. Properties of the slab are as follows: A = 1.4 x 105 mm2 St = Sb = 6.8 x 106 mm3 a = 1.2 m b = 200 mm The slab is prestressed with 820 kN force at an eccentricity e = 63 mm below the neutral axis of the section. Slab weight = 2.7 kPa Super imposed DL = 2.0 kPa Live load = 2.9 kPa The slab is simply supported on a span of 8 m. Allowable stresses at service loads are 2.0 MPa in tension and 15.5 MPa in compression. Consider 15% loss of prestressed at service loads. 1. Compute the stress (MPa) at the top fibers of the slab at the ends due to the initial prestress force. A. 2.60 Tension C. 2.83 Tension B. 1.65 Tension D. 1.74 Tension 2. Determine the resulting stress (MPa) at the top fibers of the slab at midspan due to the loads and prestress force. A. 8.85 Tension C. 9.25 Compression B. 8.85 Compression D. 9.25 Tension 3. Determine the maximum total load (kN/m) including its own weight, that the slab can be subjected to if the allowable stresses at service loads are not to be exceeded. A. 10.21 C. 11.42 B. 16.45 D. 14.43 Thanks for watching! Comment for questions and suggestions for future lecture in this series. Subscribe and hit the bell button to be notified for future posts. Check out our Review Center: https://www.facebook.com/share/1AC24W... #civilengineering #boardexam #engineering #structuralanalysis #structuralengineering #CivilEngineeringLicensureExamination #PRC #PSAD #loadanalysis #theoryofstructures #influencelines #CELESeptember2025