Concrete has a notable capacity against compression stresses but very little capacity against tension stresses (it cracks easily). One strategy to counteract this weakness in tension involves using wires or rods to prestress the concrete beam in regions where flexural tension can be anticipated. Consider the simply-supported beam shown, which has a rectangular cross section of 18" x 12". If concrete has specific weight of 150 pcf (pounds per cubic foot) determine the required tension in rod AB, which runs through the beam so that no tensile stress is developed in the concrete at its center section a-a. Neglect the size of the rod and any deflection of the beam. 16 in. B÷2 in. 18 in. 6 in. 6 in. - 4 ft- - 4 ft

Concrete has a notable capacity against compression stresses but very little capacity against tension stresses (it cracks easily). One strategy to counteract this weakness in tension involves using wires or rods to prestress the concrete beam in regions where flexural tension can be anticipated. Consider the simply-supported beam shown, which has a rectangular cross section of 18" x 12". If concrete has specific weight of 150 pcf (pounds per cubic foot) determine the required tension in rod AB, which runs through the beam so that no tensile stress is developed in the concrete at its center section a-a. Neglect the size of the rod and any deflection of the beam. 16 in. B÷2 in. 18 in. 6 in. 6 in. - 4 ft- - 4 ft

Materials Science And Engineering Properties

1st Edition

ISBN:9781111988609

Author:Charles Gilmore

Publisher:Charles Gilmore

Chapter12: Composite Materials

Section: Chapter Questions

Problem 12.7P: Estimate the transverse tensile strength of the concrete in Problem 12.6.

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