Fiber Reinforced Geopolymer Composites Suitable for Additive Manufacturing

Abstract

The conventional use of traditional concrete, especially Portland cement, has given rise to a multitude of environmental and sustainability concerns. One such concern is the significant contribution of Portland cement to global CO2 emissions, which is estimated to be around 8-9% worldwide. Given the escalating demand for concrete driven by the need for shelter and transportation, it is imperative to identify a new, sustainable, and eco-friendly alternative to traditional concrete production. In addition to the environmental impact of Portland cement, the management and recycling of construction demolition waste present another challenge for humanity. Construction demolition waste accounts for approximately one-third of the total annual waste in the European Union, and the rates of reuse vary depending on the economic strength of countries. Moreover, countries with larger economies face limitations in producing value-added goods through the reuse of construction demolition waste, so effectively addressing these material-related issues is of utmost importance. Furthermore, the traditional production methods employed in the construction industry are often slow, risky, and costly, especially in the face of modern technology. Occupational accidents associated with molded construction processes are a significant concern. Mold and labor costs also need to be optimized during the production stages. This thesis sets out to explore the impact of various fiber types on the creation of innovative and eco-friendly 3D printable geopolymer-based composites. Delving into this subject, thorough examinations have been conducted to uncover the mechanical properties, such as flexural strength, inter-layer bond strength, and compressive strength of extrusion-based 3D printed geopolymer composites. These investigations involve assessing the properties of cured mixtures over different durations under ambient conditions.

The envisioned outcome of these composite materials goes beyond conventional benefits. Notably, they strive to combat the detrimental effects of cement production on the environment, revolutionize the reuse of construction demolition waste by adding value to it, and revolutionize the construction industry through 3D production automation. Anticipated as a groundbreaking step, the development of geopolymer composites tailored for 3D-AM technology offers a beacon of hope in addressing several pressing challenges faced by the construction industry. These include mitigating global warming, alleviating excessive costs, curbing occupational accidents, and devising better solutions for construction demolition waste management.

Through this journey of exploration, the thesis seeks to present captivating solutions that promise to revolutionize the construction landscape and contribute to a more sustainable and eco-friendly future.