A W21 x 57 floor beam supports a 5-inch-thick reinforced concrete slab with an effective width b of 75 inches. Sufficient steel anchors are provided to make the beam fully composite. The 28-day compressive strength of the concrete is f,c = 4 ksi. a. Compute the moment of inertia of the transformed section. b. For a positive service load moment of 300 ft-kips, compute the stress at the top of the steel (indicate whether tension or compression), the stress at the bottom of the steel, and the stress at the top of the concrete.

A W21 x 57 floor beam supports a 5-inch-thick reinforced concrete slab with an effective width b of 75 inches. Sufficient steel anchors are provided to make the beam fully composite. The 28-day compressive strength of the concrete is f,c = 4 ksi. a. Compute the moment of inertia of the transformed section. b. For a positive service load moment of 300 ft-kips, compute the stress at the top of the steel (indicate whether tension or compression), the stress at the bottom of the steel, and the stress at the top of the concrete.

Steel Design (Activate Learning with these NEW titles from Engineering!)

6th Edition

ISBN:9781337094740

Author:Segui, William T.

Publisher:Segui, William T.

Chapter9: Composite Construction

Section: Chapter Questions

Problem 9.1.3P

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