Open Collections

Sharma Adhikari, Sarbesh

University of British Columbia

The ever-rising demands for housing and the carbon footprints associated with construction materials have increased the relevance of sustainable construction practices that use natural, low-carbon building materials. In this regard, rammed earth (RE) is a construction technology with eco-friendliness, low embodied carbon, and naturally available raw materials. Although this technique has been in practice for centuries, it is still not widely approved as a standard method due to misconceptions regarding its strength, structural design, and lack of building codes associated with the material. To meet the current standard of construction practices, builders use up to 20% Portland cement (PC); however, this does not contribute to reducing carbon footprints. This study aims to enhance the sustainability of stabilized RE by replacing energy-intensive Portland cement with eco-friendly alternatives. It also investigates the effects of binder materials such as pulp mill fly ash (PFA), a locally available waste material and hydrated lime (HL) on modern rammed earth's mechanical and thermal attributes. The two optimum RE mix designs with 5% and 10% Portland cement treated with hydrated lime and pulp mill fly ash achieved up to 85% and 200% improvement in compressive strength, respectively, compared to the control specimen with 10% Portland cement. A multicriteria analysis using the mechanical properties along with the supplementary results of freeze-thaw durability, thermal conductivity, and preliminary life cycle impact assessment (LCIA) of treated RE specimens - showed the significance of pulp mill fly ash and hydrated lime as alternative additives in reducing the cement content and enhancing the strength of RE, making the modified RE suitable for cold regions with extremely low winter temperature. Moreover, this study contributes to the wider acceptance of RE as a low-carbon material in green building construction because of its strength, durability, and sustainability.

Text

2024-12-31

Attribution-NonCommercial-NoDerivatives 4.0 International

http://hdl.handle.net/2429/86463

Civil Engineering

University of British Columbia

UBCO

http://creativecommons.org/licenses/by-nc-nd/4.0/