ЭКСПЕРИМЕНТАЛЬНЫЕ ЗЕМЛЯНЫЕ СМЕСИ ДЛЯ 3D-ПЕЧАТИ УСТОЙЧИВЫХ СТРОИТЕЛЬНЫХ КОНСТРУКЦИЙ

This article presents the results of an experimental investigation aimed at developing sustainable earth-based mixtures for 3D printing in construction. The research involved the preparation and testing of 18 different mixtures using locally available materials, including soil, lime, rice husk, marble dust, municipal solid waste incinerator ash (MSWI BA), and natural fibers such as jute, coconut, and sisal. The primary goal was to identify mixtures with optimal mechanical properties, printability, and minimal shrinkage, while considering the environmental and economic implications of using these materials. The experimental process was divided into multiple stages. Initially, each mixture was subjected to printability tests using a simple extrusion method. Then, compressive and flexural strengths were measured after 28 days of curing, followed by an investigation of shrinkage behavior. Among the tested mixtures, two were selected for further optimization, leading to the successful fabrication of 3D printed blocks. These blocks demonstrated normal mechanical performance, with compressive strengths of up to 11.04 MPa and flexural strengths of 1. MPa. Furthermore, the research also explored an economic evaluation of the materials, showing that mixtures containing lime as a binder and sisal as a reinforcing fiber achieved the best balance of cost, mechanical performance, and environmental impact. Specifically, these mixtures exhibited a compressive strength of 1.26 MPa, a carbon footprint of 0.05239 kg CO2eq/kg, and a cost of 0.137 €/kg, making them the most suitable option. Overall, the results of this study show that earth-based materials can be used in 3D printing for construction. These materials have the potential to reduce the environmental impact of the industry while maintaining sufficient mechanical properties for structural applications. Further research is needed to refine the mixture compositions, especially in terms of shrinkage control and the durability of organic fibers in alkaline environments.