A 350 mm x 700 mm concrete beam has a simple span of 10 m and prestressed with a parabolic-curved tendon with a maximum sag of 200 mm at midspan. The beam is to carry a total uniform load of 20 kN/m including its own weight. Assume tension stresses as positive and compressive as negative. Determine the following: 1. The effective prestress required for the beam to have no deflection on the given load. 2. The stress in the bottom fiber of the section at midspan for the above condition. 3. The value of the concentrated load to be added at midspan in order that no tension will occur in the section.

A 350 mm x 700 mm concrete beam has a simple span of 10 m and prestressed with a parabolic-curved tendon with a maximum sag of 200 mm at midspan. The beam is to carry a total uniform load of 20 kN/m including its own weight. Assume tension stresses as positive and compressive as negative. Determine the following: 1. The effective prestress required for the beam to have no deflection on the given load. 2. The stress in the bottom fiber of the section at midspan for the above condition. 3. The value of the concentrated load to be added at midspan in order that no tension will occur in the section.

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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