Thermal performance exploration of 3D printed cob

ABSTRACT This paper investigates the thermal properties of 3D printed Cob, a monolithic earth construction technique based on robotically extruded subsoil and locally available organic fibres. The relevance of 3D printed earthen construction materials and the transition from vernacular construction towards a digitally-enabled process are critically discussed. The use of robotic manufacturing is outlined and the methodology to produce the necessary samples for thermal measurement is detailed. The results of the 3D printed samples are compared with traditionally-constructed Cob material of the same dimensions. The assessment has revealed strong potential for 3D printed cob as compared to its manually constructed counterparts in terms of thermal conductivity. Moreover, the testing process has helped in identifying several challenges in the 3D printing process of cob and the assessment of its thermal properties, which will ultimately bring the work closer to full-scale applications.

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