Investigation of mechanical properties of fiber concrete exposed cold weather to fresh

Traditional concrete is typically poor in fatigue, cavitation, (cavity, hollow, pit), wear, impact strength, post-cracking load bearing strength and toughness. Where these properties of concrete are clearly required, the concrete is reinforced by improving the weak properties of the concrete as a result of the addition of high-quality fibers made of different materials into the concrete. In order to achieve efficient and accurate results, concrete design is important as well as it is important in concrete casting conditions. During the pouring of concrete; the average temperature falls below + 5ºC for three consecutive days is defined as cold air in TS 1248 standard (TS 1248). Over 3 consecutive days; if the daily average air temperature is less than 5 ºC or the temperature does not exceed 10 ºC for more than half of a 24 hour period, these conditions are also defined as cold weather conditions (ACI 306, 1997). When the fresh concrete is poured, the temperature of the environment increases the time, the hydration slows down and the rate of gain decreases, and the mold take time is delayed. Hydration stops with the freezing of the fresh concrete and the water in it. When the concrete under the influence of the frost is dissolved, hydration can be resumed, but the adherence is greatly reduced at the cement-pulp-aggregate and cement-pulp-reinforcement interfaces. This leads to a decrease in concrete strength. Because of these reasons; In this study; the aim of this course is to investigate the change in mechanical properties of fibrous concretes produced under the influence of fresh air under fresh air. This For this purpose, the concrete produced by adding steel and polypropylene fibers will be exposed to fresh frost at 0ºC, -5ºC and -10ºC. In order to compare the change in mechanical properties with the effect of cold air, fiber and fiber samples will be produced in laboratory conditions. Steel and Polypropylene fibers will be used in different lengths and in different ratios in order to see the contribution of fiber properties to mechanical properties. Bending strength, compressive strength and energy absorption capacity (toughness) will be determined on the samples produced. The mechanical properties of the non-fiber reference concrete and the fibrous concrete produced will be investigated and the changes will be determined. As a result, it has been determined that the temperature value of concrete is negatively affected by the change of the temperature value. The fiber additive used in concrete has a positive effect on the mechanical properties.