The beam shown has a 30-ft simple span, fc' 5000 psi, fpu = 250,000 psi, and the %3D initial prestress is 160,000 psi, fpy 0.85fpu, and 10% losses. %3D (a) Calculate the concrete stresses at the top and bottom of the beam at midspan immediately after the tendons are cut. (b) Recalculate the stresses at midspan after assumed prestress losses in the tendons of 20%. (c) What maximum service live load can this beam support in addition to its own weight if allowable stresses of 0.6fc' in compression and 12fc' in tension are permitted? 21 in. 24 in. 0.9 in.2 3 in. 14 in.-

The beam shown has a 30-ft simple span, fc' 5000 psi, fpu = 250,000 psi, and the %3D initial prestress is 160,000 psi, fpy 0.85fpu, and 10% losses. %3D (a) Calculate the concrete stresses at the top and bottom of the beam at midspan immediately after the tendons are cut. (b) Recalculate the stresses at midspan after assumed prestress losses in the tendons of 20%. (c) What maximum service live load can this beam support in addition to its own weight if allowable stresses of 0.6fc' in compression and 12fc' in tension are permitted? 21 in. 24 in. 0.9 in.2 3 in. 14 in.-

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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