Experimental studies of short concrete reinforced steel fiber beams under bending

Abstract

This paper presents the results of a test program on 24 concrete beams with a cross section of 15 x 15 cm. Those are divided into two groups of 12 beams. Group I has a steel fiber content of 40 kg/m³ while Group II uses 60 kg/m³ of steel fibers. The tests consider three sets of beam lengths: 300 mm, 500 mm and 800 mm. The beams were submitted to bending aiming at investigating shear stresses, bending, strain energy, toughness, scale effect and fracture energy. Group II showed a slightly higher resistance to rupture than Group I. However, the smaller the length, the larger the influence of the fiber content. The largest fiber content gave the concrete higher resistance when submitted to bending and shear, especially for the smaller lengths. Both strain and fracture energy, however, show considerable differences for smaller lengths, but are almost the same for the 800 mm beams. Toughness shows improvement in the longer beams and a reduction of this property in the shorter beam from Group II.

The Effect of Steel Fiber and Internally Curing on the Strength of Self-Consolidated Concrete

“…This gives an indication of good concrete (with low permeability) and it may be attributed to the continuous hydration of cement which decreases the absorption of SCC, as well as, due to the dense microstructure of SCC with low W/C ratio used and the presence of silica fume. This causes modification to the microstructure of concrete, reduces the capillary pores leading to better packing, increase the density and lead to a reduction in the absorption percentage (Teknik, D. B., 2005;Nehdi, M., & Ladanchuk, J. D., 2004) The absorption test was carried on 3 mixes 1, 2 and 5 to conclude the effect of steel fibers and internal curing by fine LWA on the absorption results. Besides the decrease in the absorption of the Mix 5 may be due to the increase in super-plasticizers' dosage to retain and maintain their flowability and passing ability of this mix in the fresh state.…”

Experimental Investigation of the Structural Performance of Concrete Containing Cellulose Fibers and the Anti-corrosive Effect of Green Corrosion Inhibitors

“…Concrete is an important construction material which possesses a very high compressive strength and a very low tensile strength (about one-tenth of compressive strength) and is consumed to a tune of 7.5 billion tons annually [1,2]. They withstand heavy loads until they are cracked and after which they do not transfer stress leading to collapse.…”