The Effects of Cracks on the Modulus of Rupture of Concrete

Zarak Khan Kasi, Saeedullah Jan Mandokhail, Nawaz Ali Kakar, Marjan Gul Kakar, Meer Hamza Khan Jogezai

Abstract


The purpose of this study was to experimentally investigate the effects of cracking on the modulus of rupture (MOR) of concrete. When a structural member (e.g. column member) is subjected to dynamic loading, the tensile and compressive parts are interconverted on each stress reversal. The cracks may initiate in the tensile part due to the cyclic loading depending on the magnitude of stresses. Such understanding is critical in understanding the overall effects of cyclic loading on the building and on the strength of concrete. In this paper, the effect of such cracks on MOR were studied by conducting detailed laboratory tests. Reinforced beams were prepared by using three different concrete mix designs. The center point load flexural tests on beams were conducted by producing initial cracks in the tension zone and then switching the cracked tensile zone into compressive zone to study the effects of cracks on the MOR. The MOR of cracked and uncracked beams were compared. The experimental results shown that the cracks had no pronounced effect on MOR.

Keywords


Cracks; Modulus of Rupture; Reversal Zone; Compressive Strength;

Full Text:

PDF

References


ACI. (2008). Building code requirements for structural concrete and commentary. ACI 318.

ASTM. (2002a). Standard test method for flexural strength of concrete. ASTM C 78, West

Conshohocken, PA.

ASTM. (2002b). Standard test method for flexural strength of concrete (Using Simple Beam With

Center-Point Loading). ASTM C 239, West Conshohocken, PA.

ASTM. (2003) Standard Specification for Concrete Aggregates. ASTM C 33, West Conshohocken, PA.

ASTM. (2005). Standard test method for compressive strength of cylindrical concrete specimens. ASTM

C 39/C 39M, West Conshohocken, PA.

ASTM. (2012) Standard Specification for Concrete Made by Volumetric Batching and Continuous

Mixing. ASTM C 685/C 685M - 01, West Conshohocken, PA.

Issa CA, Gerges NN, Fawaz S. (2014). The effect of concrete vertical construction joints on the modulus

of rupture. Case Studies in Construction Materials 1:25-32.

Novak D, Bazant ZP, Vitek JL. (2002). Experimental-analytical size-dependent prediction of modulus

of rupture of concrete. Non-traditional Cement and Concrete, ed by V Bilek and Z Kersner, ISBN:80-214.

Pytel A, Singer FL. (1978). Strength of materials, 4th Edition. Harpercollins College Div, 4th edition.



Contacts | Feedback
© 2002-2014 BUITEMS