A pre-stressed hollow core slab has property as follows: A = 108,864 mm2, St = Sb = 4,115,789 mm3. The slab is prestressed with 580 KN force at an eccentricity, e=42 mm below the centroid of the section. The weight of the slab is 3.74 kPa, SDL is 3.1 kPa, and live load is 3.8 kPa. The slab is simply supported on bearings at L=7.9m. Allowable stresses at service loads are 3.4 MPa in tension and 18.2 MPa in compression. Consider 20% loss of prestress at service loads. Determine the resulting stress at the bottom fibers of the slab at L/4 from the center of bearings, in MPa. Do not round-off during the course of solving. Answer in two decimal places. Use WSD method.

A pre-stressed hollow core slab has property as follows: A = 108,864 mm2, St = Sb = 4,115,789 mm3. The slab is prestressed with 580 KN force at an eccentricity, e=42 mm below the centroid of the section. The weight of the slab is 3.74 kPa, SDL is 3.1 kPa, and live load is 3.8 kPa. The slab is simply supported on bearings at L=7.9m. Allowable stresses at service loads are 3.4 MPa in tension and 18.2 MPa in compression. Consider 20% loss of prestress at service loads. Determine the resulting stress at the bottom fibers of the slab at L/4 from the center of bearings, in MPa. Do not round-off during the course of solving. Answer in two decimal places. Use WSD method.

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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