Fire response of hybrid fiber reinforced concrete to high temperature

Abstract

The building industry offers a wide range of materials whose structural behavior is more or less affected by temperature. While the knowledge and experience with concrete behavior under ambient temperature are well-known, the behavior under elevated temperature has to be deeply investigated. The contribution focuses on observing the behavior of hybrid fiber reinforced concrete under ambient and elevated temperature with the aim to determine the mechanical properties of the material. The experimental work carried out was divided into several phases. First of all it was necessary to leave the produced specimens aging and drying in order to minimize the risk of unexpected damage caused by vapour expansion during heating. Then, the heat transport test was performed on a few specimens to determine the time required for uniform heating the specimens up to 400°C and 600 °C. In the last phase the conventional testing methods were undertaken to determine the mechanical properties of the concrete composite at ambient and elevated temperature. Compression and split tension tests were conducted on the 150 mm cubes. Based on the results, the peak and residual strength of the material were determined for various temperature levels. The obtained findings contribute to improving the knowledge in the field of both concrete structures exposed to high temperature and structural behavior of fiber reinforced concrete. The findings can be also utilized in case of the structural design of concrete structures with the high risk of fire loading.