Assignment Questions: 1. A prestressed concrete beam supports a live load of 6 kN/m over a simply supported span of 8m. The beam has an l- section with an overall depth of 430 mm. The thickness of the flange and web are 65 mm and 75 mm respectively. The width of the flange is 190 mm. The beam is to be pre- stressed by an effective forcce of 250 kN at a suitable eccentricity such that the resultant stress at the soffit of the beam at the center of the span is zero. (a) Find the eccentricity required for the force. (b) If the tendon is concentric, what should be the magnitude of the pre-stressing force for the resultant stress to be zero at the bottom fiber of the central span section.

Assignment Questions: 1. A prestressed concrete beam supports a live load of 6 kN/m over a simply supported span of 8m. The beam has an l- section with an overall depth of 430 mm. The thickness of the flange and web are 65 mm and 75 mm respectively. The width of the flange is 190 mm. The beam is to be pre- stressed by an effective forcce of 250 kN at a suitable eccentricity such that the resultant stress at the soffit of the beam at the center of the span is zero. (a) Find the eccentricity required for the force. (b) If the tendon is concentric, what should be the magnitude of the pre-stressing force for the resultant stress to be zero at the bottom fiber of the central span 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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