Utilization of liquid crystal display (LCD) glass waste in concrete: A review

As the demand for display devices increases, the disposal of liquid crystal display (LCD) glass waste becomes an emerging issue. It is thus necessary to make efforts to recycle bulk LCD glass waste. The construction industry can propose a solution to this by using LCD glass waste as an alternative resource for construction materials. This paper presents a state-of-the-art review on the utilization of LCD glass waste as replacements for cement and fine aggregate. Its applications in special types of concrete, e.g., ultra-high-performance concrete (UHPC), self-compacting concrete, and geopolymers, are also investigated. Thanks to the high pozzolanicity with abundant alumina, the LCD glass powder can partially replace the cement in a classical concrete and filler of UHPC. The matrix modified with the LCD glass powder is effective in improving the medium- to long-term mechanical strength (generally at a replacement level of up to 10% or 20%) and the overall durability, with respect to alkali-silica reaction expansions, sulfate attacks, and chloride ion penetration, and freeze–thaw, as well as the pull-out resistance. However, the alternative use of LCD glass powder in metakaolin negatively affects the mechanical strength of the geopolymer, owing to the increased heterogeneity, pore size, and volume. The use of LCD glass waste as sand decreases the mechanical strength in general but leads to better workability, durability, and volume stability. Thus, LCD glass waste can be used as a new alternative ingredient for concrete, as a replacement for cementitious materials or sand.