STRUCTURAL BEHVAIOR OF REINFORCED CONCRETE BEAMS CAST USING BLENDED CEMENT

Document Type : Original Article

Authors

1 Civil Engineering Department, Faculty of Engineering, Menoufia University, Egypt

2 Ministry of Water Resources and Irrigation, Dakahlya, Egypt

Abstract

An experimental study has been carried out in the present work to study the structural behavior of
reinforced concrete beams cast using blended cement concrete. The eight tested beams were 160
cm long × 20 cm deep × 12 cm wide. The test beams were reinforced with two different steel
reinforcement ratios of 0.70% and 1.0%. Two beams were control beams cast using Portland
cement and the other six beams were cast using blended cement incorporating 5%, 10% and 15%
dolomite powder as cement replacement. To achieve the aim of the research; all beams were tested
under 4-point loading until failure and the following measurements have been recorded during
testing the beams for each load increment; the compressive and tensile strains in concrete and
steel, and mid-span deflection. The propagation of cracks was marked on the side and soffit of the
beam. The results of monitoring the tensile and compressive strains, mid-span deflection and
cracking pattern are presented. The results demonstrated that the 5 percent replacement ratio did
not influence the structural behavior, while the ultimate loads and stiffness were reduced as the 10
and 15 percent replacement ratios. On the other hand, the cracking characteristics and failure mode
were not influenced by the cement replacement.

Keywords