Manuel Jesus

Three-dimensional printing (3DP) represents a significant innovation in the construction sector, offering substantial benefits in terms of efficiency, customisation, and sustainability. In the context of built heritage rehabilitation, it is capable of accurately reproducing architectural elements, facilitating conservation efforts, while minimising waste and resource consumption. However, in this field, ensuring material compatibility with original structures is essential. This study explores the development and optimisation of lime and cement-based mortars for 3DP applications, focusing on their physical and mechanical performances (on moulded specimens) for use in replicating elements of a renowned Portuguese theatre. Laboratory testing supports the selection of suitable mortar compositions, aiming to balance performance and fidelity to historical construction practices. This research seeks to contribute to explore the potential of 3DP for heritage conservation, promoting innovative, durable, and culturally sensitive restoration strategies.

In this study, we ask if there are broadly scalable methods for additively manufacturing low-carbon, climate-specific architecture that are thermally and structurally performative for housing. We then demonstrate that high-performance, hierarchical building elements can be produced from extremely low-cost, low-carbon materials like earth using increasingly available 3D printing tools. We present a set of novel design methods and building systems from the scale of a brick to the scale of a wall, utilizing a combination of simulation-driven design and additive manufacturing with earth and clay. By leveraging materials readily available in all climates, bespoke, simulation-driven building elements could be manufactured from these low or no-cost materials to create performative, low-carbon buildings. By presenting a methodology for material and fabrication-aware energy simulation for additive manufacturing, this work provides scalable groundwork for future studies across climates and local building requirements.

Purpose: The paper seeks to bridge the already familiar benefits of 3D printing (3DP) to the rehabilitation of cultural heritage, still based on the use of complex and expensive handcrafted techniques and scarce materials.Design/methodology/approach: A compilation of different information on frequent anomalies in cultural heritage buildings and commonly used materials is conducted; subsequently, some innovative techniques used in the construction sector (3DP and 3D scanning) are addressed, as well as some case studies related to the rehabilitation of cultural heritage building elements, leading to a reflection on the opportunities and challenges of this application within these types of buildings.Findings: The compilation of information summarised in the paper provided a clear reflection on the great potential of 3DP for cultural heritage rehabilitation, requiring the development of new mixtures (lime mortars, for example) compatible with the existing surface and, eventually, incorporating some residues that may improve interesting properties; the design of different extruders, compatible with the new mixtures developed and the articulation of 3D printers with the available mapping tools (photogrammetry and laser scanning) to reproduce the component as accurately as possible.Originality/value: This paper sets the path for a new application of 3DP in construction, namely in the field of cultural heritage rehabilitation, by identifying some key opportunities, challenges and for designing the process flow associated with the different technologies involved.