A normal-weight concrete specimen tested at 28 days yielded the following results: (a) A 6 in. (diameter) x 12 in. (height) concrete cylinder failed at an axial compressive force of 105,000 Ibf. How much is the ultimate compressive strength? (b) A 6 in. square unreinforced beam section failed at a force of 5400 lbf on a 21 in. span length. A third-point loading test was used, and the fracture occurred within the middle third. How much is modulus of rupture? (c) What is the ratio of the modulus of rupture in (b) to the compressive strength in (a)? (d) Use the compressive strength in (a) to calculate the approximate value of the modulus of rupture per ACI318-19. What is the ratio of your result here to the value in (b)? What conclusion can you make here?

A normal-weight concrete specimen tested at 28 days yielded the following results: (a) A 6 in. (diameter) x 12 in. (height) concrete cylinder failed at an axial compressive force of 105,000 Ibf. How much is the ultimate compressive strength? (b) A 6 in. square unreinforced beam section failed at a force of 5400 lbf on a 21 in. span length. A third-point loading test was used, and the fracture occurred within the middle third. How much is modulus of rupture? (c) What is the ratio of the modulus of rupture in (b) to the compressive strength in (a)? (d) Use the compressive strength in (a) to calculate the approximate value of the modulus of rupture per ACI318-19. What is the ratio of your result here to the value in (b)? What conclusion can you make here?

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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