In the rapidly evolving world of construction technology, a groundbreaking study is shedding light on the potential of recycled materials to revolutionize 3D printing in the industry. Researchers from the Programa de Pós-Graduação em Engenharia Civil (PGECiv) at Universidade Estadual de Londrina (UEL) in Brazil have published a study in the MATEC Web of Conferences (which translates to Materials Science and Technology Conference Proceedings), exploring the rheological behavior of 3D-printable mortars incorporating fine recycled concrete aggregates (FRCA). The study, led by Eduardo Kloeckner, delves into the impact of substituting 25% and 50% of traditional aggregates with FRCA on key rheological parameters, offering insights that could significantly influence the future of sustainable construction.
The research focuses on understanding how the incorporation of FRCA affects the flow spread, penetration resistance, shear stress, and yield stress of 3D-printable mortars over time. These parameters are crucial for ensuring the extrudability and printability of the mortars, directly impacting the buildability and stability of printed structures. “The flow spread test evaluated the mortar’s consistency and ability to maintain workability over time, essential for continuous extrusion during the printing process,” explains Kloeckner. This aspect is particularly important for the energy sector, where the construction of complex and large-scale structures often requires continuous and uninterrupted printing processes.
The study also highlights the significance of the penetration resistance test, which assesses the stiffening rate of the mortar. This provides valuable insights into the setting time and early strength development of the material, which are critical for the structural integrity of printed buildings. “The penetration resistance test assessed the stiffening rate of the mortar, providing insights into setting time and early strength development,” adds Kloeckner. Understanding these properties can help optimize the printing process, reducing the risk of deformation or collapse and ensuring the stability of subsequent layers.
One of the most compelling findings of the study is the impact of FRCA on the yield stress of the mortars. The vane and slug tests conducted by the researchers measured the yield stress, a critical parameter for ensuring buildability and layer stability. The results indicate that mortars containing FRCA exhibit differences in flow retention and yield stress evolution, which are key factors influencing extrudability and printability. “The vane and slug tests measured yield stress, a critical parameter for ensuring buildability and layer stability, indicating the mixture’s capacity to support subsequent layers without deformation or collapse,” notes Kloeckner.
The commercial implications of this research are substantial. As the construction industry increasingly turns to sustainable and eco-friendly materials, the use of FRCA in 3D printing could significantly reduce the environmental impact of building projects. This is particularly relevant for the energy sector, where the construction of renewable energy infrastructure often requires large quantities of materials. By incorporating FRCA into 3D-printable mortars, construction companies can not only reduce their carbon footprint but also lower material costs, making sustainable construction more economically viable.
The study published in the MATEC Web of Conferences offers a promising glimpse into the future of construction technology. As researchers continue to explore the potential of recycled materials in 3D printing, the industry stands to benefit from more sustainable, cost-effective, and efficient building practices. The findings of this research could pave the way for innovative solutions that address the growing demand for sustainable construction in the energy sector and beyond. As Kloeckner aptly puts it, “This research highlights the potential of recycled aggregates to enhance the rheological properties of 3D-printable mortars, offering a sustainable and efficient alternative for the construction industry.”