Effect of steel fiber and silica fume on hardened concrete compressive and flexural strength

الملخص EN

Fiber reinforced concrete (FRC) may be defined as a composite materials made with Portland cement, aggregate, and incorporating discrete discontinuous fibers and silica fume.

In this paper an attempt is made at 300°C to present the results of an experimental investigation carried out on (FRC).

While Fiber content was used as (0%, 0.5%and1%) by weight of mix and silica fume was used as (0%, 5% and 10%) by weight of cement.

Effect of the addition of silica fume and steel fiber on the various strengths of concrete was studied.

The strengths considered for investigation are compressive strength and flexural strength.

Cubes of size (150) mm for compressive strength; beams of size (100 mm x 100 mm x 500 mm) for flexural strength, were used as specimens.

All the specimens were water cured for 28 days and tested subsequently.

The compressive strength decreases by about (18%, 18.1% , 20% ) for (0% steel fiber) at 300°C with no silica fume, 5% and 10% silica fume respectively and the compressive strength decreases by about (16%, 20 %, 24% ) for (0.5% steel fiber) at 300°C with no silica fume, 5%and 10%silica fume respectively while the compressive strength decreases by about (15%, 15.5%, 16%) for (1%steel fiber) at 300°C with no silica fume, 5%and 10%silica fume respectively.

The flexure strength decreases by about (40.3%, 39.9%, 41%) for (0%steel fiber) at 300°C with no silica fume, 5%and 10% silica fume respectively and the flexure strength decreases by about (38.5%, 38.0% , 38.1%) for (0.5%steel fiber) at 300°C with no silica fume, 5%and 10%silica fume respectively, while flexure strength decreases by about (35.8%, 36%, 37.07%) for (1%steel fiber) at 300°C at 300°C with no silica fume, 5%and 10%silica fume respectively.

All the above results are compared with cubes and prisms tested at roomtemperature (25 °C).