Anisotropic hygrothermal properties of 3D printed concrete

3D Concrete Printing (3DCP) is a method for constructing concrete components in layers. There is a knowledge gap regarding hygrothermal anisotropies introduced during the printing process. Standard experimental procedures were applied to quantify the hygrothermal properties of a 3DCP slab that was printed and cut into samples for testing. The partial immersion (ISO 15148) and MTPS (ASTM D7984) methods were applied to quantify water absorption and thermal conductivity through each major sample orientation. Results demonstrate anisotropic hygrothermal properties, with a 3.6x difference in water absorption and a 1.5x difference in thermal conductivity. Findings indicate a boundary resistance between print layers that inhibits vertical imbibition and, by extension, rising damp.