A Study on the Applicability of Waste Glass Wool and Waste Mineral Wool as Fiber Reinforcement

Recently, the handling of waste industrial resources has become an issue, and the importance of sustainable resources has increased. Among these waste industrial materials are glass wool and mineral wool, which are fibrous materials used as insulation materials with characteristics such as sound absorption, insulation, and non-flammability. However, after their service life, glass wool and mineral wool used for insulation are generally buried or incinerated, causing problems such as air and soil contamination. This research was conducted to examine the applicability of waste glass wool and mineral wool obtained from expired insulation as fiber reinforcement in cement concrete. The research aimed to evaluate the fresh concrete properties, strength properties, and durability properties by adding waste glass wool and waste mineral wool up to 0.5-2.0% of the cement weight. Regarding the slump and air content of fresh concrete, the results showed that the addition of waste fibers within this range did not significantly affect the air content. However, the slump decreased as the addition amount increased due to the high absorption, which is a characteristic of the fibers. In addition, the evaluation of strength revealed that the incorporation of fibers decreased the compressive strength compared to the reference concrete. However, the tensile strength increased due to the load-supporting function of the waste fibers. In the evaluation of freezing-thawing resistance and chloride ion penetration resistance, it was confirmed that the freezing-thawing resistance improved in all cases where waste glass wool was added. The chloride ion penetration resistance was found to be similar to that of the reference concrete. However, in the case of waste mineral wool, it was observed that an addition rate of more than 2.0% of fibers was required to ensure freezing-thawing resistance. As the addition rate increased, the total charge passed (permeability) increased significantly, leading to a decrease in chloride ion penetration resistance.