Effect of high standard of temperature on the hardened needled concrete

الملخص EN

Fibers are usually used to reinforce concrete.

The study shows the using of needles for reinforcing high-strength concrete (60MPa) when the samples are exposed to temperatures (100°C and 400°C) with a percentage of needles (0 %, 0.5 % and 1 %) compared with the conditions of room temperature (25°C).

They study shows that the compressive strength decreases by about (0.94 % and 17.6 %) for (0 % needle (steel fiber)) at 100°C and 400°C, respectively.

The compressive strength decreases by about (1.7 % and 15.9 %) for (0.5 % needle (steel fiber)) at100°C and 400°C, respectively.

The compressive strength decreases by about (0.3 % and 14.2 %) for (1 % needle (steel fiber)) at 100°C and 400°C, respectively.

All the above-mentioned results are compared with cubes tested at room temperature (25°C).

Based on the results of this work, the tensile strength decreases by about (0.49% and 6.65 %) for (0 % needle (steel fiber)) at 100°C and 400°C, respectively.

The tensile strength decreases by about (0.73 % and 6.1 %) for (0.5 % needle (steel fiber)) at 100°C and 400°C, respectively.

The tensile strength decreases by about (0.24 % and 5.54 %) for (1 % needle (steel fiber)) at 100°C and 400°C, respectively.

All the above-mentioned results are compared with cubes tested at room temperature (25 °C).

The flexural strength decreases by about (1.08 % and 26 %) for (0 % needle (steel fiber)) at 100°C and 400°C, respectively.

The flexural strength decreases by about (2.1 % and 26.3 %) for (0.5 % needle (steel fiber)) at 100°C and 400°C, respectively.

The flexural strength decreases by about (3.1 % and 24.7 %) for (1 % needle (steel fiber)) at 100°C and 400°C, respectively.

All the above-mentioned results are compared with cubes tested at room temperature (25°C).