AN EXPERIMENTAL STUDY ON THE THERMAL CONDUCTIVITY OF CELLULAR LIGHTWEIGHT CONCRETE OF DIFFERING AIR-VOID SIZES AND SHAPES

Abstract

Globally, carbon emissions have been on the rise, especially after the pandemic, where many businesses are eager to operate again. It is predicted that it will continue to rise given the trend computed by the International Energy Agency. Singapore is no different, where it observes a growth in carbon emissions within its own country. Energy consumption has been known to be one of the leading factors contributing to carbon emissions. Hence, by reducing the consumption in energy, it can also reduce production in carbon emissions. Studies have shown that building consumes large amounts of energy, especially for cooling purposes in hotter climates. Singapore, being a tropical country, heavily relies on air-conditioning to cool its building. It is therefore crucial that crucial to sought ways to lower building energy consumption for cooling purposes. One way this can be done is through the improvement of thermal insulation of building envelopes. Conventional building materials used to insulate the building are multi-layered wall systems, where a combination of concrete and insulating materials is used. Research into novel materials such as cellular lightweight concrete has proven to have excellent thermal insulating abilities. Many studies have been done to achieve the optimal thermo-mechanical property in cellular lightweight concrete as it can eventually replace multi-layered wall systems with a mono-layered cellular lightweight concrete as it can also serve as a structural building element. In this paper, an alternative cellular lightweight concrete (CLC) design was investigated into as typical CLC, which is foamed concrete, has many challenges in achieving the optimal thermo-mechanical property. The focused design was Voronoi, a plant-inspired, non-periodic pattern. It was compared to Honeycomb’s periodic pattern, and subsequently to foamed concrete and plain mortar. Results showed Voronoi CLC having the optimal thermo-mechanical property in the medium porosity range, followed by Honeycomb CLC in both low and high porosity levels. Hence, both Honeycomb and Voronoi CLCs have the potential of being the next ideal building material for thermo-mechanical purposes.