A rectangular beam has a width 355 mm and a 660 mm depth on a simple span of 12.0 m. The straight tendons are placed at an eccentricity 125 mm below the N.A. (end-to-end of the beam), or 205 mm above the bottom of the beam. The initial prestressing force is 1,200,000 N. The allowable top concrete stress is -14.0 MPa (Compression) while the bottom concrete fiber stress is +1.50 MPa (Tension) both acting at the point of maximum moment. Assuming a loss of stress of 20 % of the initial prestressing force, determine the following: Situational Problem 1: the top concrete fiber stress at service stage (live load stage) in MPa; Situational Problem 2: the bottom concrete fiber stress at service stage (live load stage) in MPa; Situational Problem 3: the moment capacity of the beam as required by the fiber stress in Situational Problem 1, in kN m;

A rectangular beam has a width 355 mm and a 660 mm depth on a simple span of 12.0 m. The straight tendons are placed at an eccentricity 125 mm below the N.A. (end-to-end of the beam), or 205 mm above the bottom of the beam. The initial prestressing force is 1,200,000 N. The allowable top concrete stress is -14.0 MPa (Compression) while the bottom concrete fiber stress is +1.50 MPa (Tension) both acting at the point of maximum moment. Assuming a loss of stress of 20 % of the initial prestressing force, determine the following: Situational Problem 1: the top concrete fiber stress at service stage (live load stage) in MPa; Situational Problem 2: the bottom concrete fiber stress at service stage (live load stage) in MPa; Situational Problem 3: the moment capacity of the beam as required by the fiber stress in Situational Problem 1, in kN m;

Structural Analysis

6th Edition

ISBN:9781337630931

Author:KASSIMALI, Aslam.

Publisher:KASSIMALI, Aslam.

Chapter2: Loads On Structures

Section: Chapter Questions

Problem 1P

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