A rigid steel plate is supported by three posts of high-strength concrete each having an effective cross-sectional area A = 40,000 mm2 and length L = 2 m (see figure). Before the load P is applied, the middle post is shorter than the others by an amount s = 1.0 mm. The allowable compressive stress in the concrete is 20 MPa and E of concrete is 30 GPa. What is the minimum load P (kN) needed to close the gap?

A rigid steel plate is supported by three posts of high-strength concrete each having an effective cross-sectional area A = 40,000 mm2 and length L = 2 m (see figure). Before the load P is applied, the middle post is shorter than the others by an amount s = 1.0 mm. The allowable compressive stress in the concrete is 20 MPa and E of concrete is 30 GPa. What is the minimum load P (kN) needed to close the gap?

Mechanics of Materials (MindTap Course List)

9th Edition

ISBN:9781337093347

Author:Barry J. Goodno, James M. Gere

Publisher:Barry J. Goodno, James M. Gere

Chapter2: Axially Loaded Members

Section: Chapter Questions

Problem 2.12.8P: A rigid bar ACB is supported on a fulcrum at C and loaded by a Force P at end B (see figure). Three...

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