Effect of Mixture Ratios on Thermal Behaviours of High Strength Concrete Walls Exposed to Fire on Foreside

This paper aims at evaluating thermal behaviors of high strength concrete walls exposed to fire on foreside having different mixture ratios. Toward that goal, fire tests of walls are performed on concrete walls for 2 hours in heating furnace according to the international standard ISO-834. Variables of the study are mixture ratios and locations of thermocouples. First, two different mixture ratios are used for high compressive strength concretes with targeting 28 days compressive strength of 40MPa and 60MPa. One of the mixtures (targeting 28 days compressive strength of 60MPa) includes Polypropylene fibers to prevent explosion. Second, 12 thermocouples are installed at 3 different locations of concrete walls and each location has thermocouples at 3 different distances from the fire exposed surface (20mm, 40mm and 100mm). Size of the wall is 1200mm (H) × 600mm (W) × 200mm (T). From the fire tests, time-temperature curves are obtained at different locations. The test results show that temperatures vary depending on locations and are significantly affected by mixture ratios.