Abstract:

Concrete is the most extensively used construction material today, and cement is used as the bonding agent in the concrete production. Use of silica fume in steel fiber concretes is suitable for high-strength and high-quality concrete production. In this study, tests were conducted using silica fume in steel fiber concretes by 0 %, 5 %, 10 % and 15 % via replacement with cement. CEM I 42.5 N cement and steel fiber were used in the concrete produced during the tests. Samples were selected from C 25 class in which water/cement ratio was 0.50 and produced by being subjected to vibration. Test samples were subjected to a flexural test from their midpoints and a compression test from the edges on prism samples produced at sizes of 100 mm x l00 mm x 500 mm. 7 day and 28 day flexural and compression strength tests of the concretes produced were measured. Besides, hydration products in concrete were observed with scanning electron microscope, energy dispersive spectrometry, and x-ray diffraction. As a result, it was determined that as the amount of silica fume increased, there was an increase in flexural and compressive strength.

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