Development of Self-Compacting Translucent Concrete Incorporating Recycled Glass Aggregate for Sustainable Construction

Abstract

Worldwide, artificial lighting consumes around 19% of the total delivered electricity. The electric lighting demand has constantly been increasing with the increase in the population, urbanization, and construction of high-rise buildings. The production of electricity contributes to the increase in the greenhouse gas emissions. Translucent concrete is an innovative solution towards significantly reducing the need for artificial lighting by allowing transmission of natural light into building’s interior environment when the translucent concrete is used as structural façades and architectural walls. The overall objective of this research was developing translucent concrete incorporating recycled glass aggregate as substitution of natural fine aggregate using selfcompacting mortar (SCM). The use of recycled glass aggregate (RGA) in SCM aims to reverse the adverse environmental effects of waste glass, conserve natural resources and as a viable solution towards sustainable solid waste disposal and management. Limestone powder (LP) was used as filler that constitutes 20% – 30% of the powder volume to reduce the amount of cement. The SCM mixes were designed and evaluated based on Japanese mix design method and EFNARC, respectively. The light transmittance performance of plastic optical fiber (POF) based translucent concrete was evaluated using an electrical circuit test setup with a light dependent resistor (LDR). Structural performance of translucent concrete panels/ façades was also examined to assess ductility and failure mechanism under flexural loading. The experimental test results showed that the slump flow of SCM mixes decreased and V-funnel flow time increased when the content of recycled glass aggregate (RGA) increased. The bulk density, compressive strength, flexural strength, water absorption and sorptivity of SCM mixes were decreased as RGA content increased. Moreover, the accelerated mortar bar test results showed that the expansion due to alkali-silica reaction (ASR) of SCM mixes increased as the content of RGA increased although the expansion of all mixes was within the acceptable limit and potentially innocuous. The bulk density of translucent concrete was found to decrease marginally with increases the volume ratio of plastic optical fibers (POF). It was also clearly observed that all the translucent concrete specimens exhibited compressive and flexural strength of lower than the reference concrete. On average, the 28 days compressive and flexural strength was 8% – 24% lower for the translucent concrete than for the reference concrete. The light transmittance test showed that the light transmittance performance of the translucent concrete significantly depends on the percentage volume of optical fibers incorporated. The inclusion of POF improves the ductility and flexural toughness of concrete panels. The flexural toughness and toughness factor were 11% – 22% higher in translucent concrete panels than in the reference concrete panel. Generally, at replacement ratio up to 30%, recycled glass aggregate is viable for production of SCM and translucent concrete with good workability, sufficient strength, and durability. The translucent concrete panels/ façade developed in this study are apt for application in load bearing and non-load bearing architectural walls of green buildings, underground stations, in structural walls of banks, prisons, and museums to increase security and supervision as well as safety.