Engineering Properties Influencing Clayey Materials for Additive Manufacturing (2018-07)¶

The objective of the study is to further define the engineering properties of clayey materials that influence performance when used in additive manufacturing. Limited existing literature explored the workability, extrudability and buildability of these material mixes to determine the acceptable ranges to be 3D-printed. This study was designed to deepen the understanding of fresh properties of clayey materials. Also, this work differs in that sustainable materials were used including clay and dredged material from the Maumee River in Toledo, Ohio. Plus, no chemical admixtures were used as found in many other studies. Extrudability, buildability, and workability tests were performed on the clay, and dredged material at varying water to binder ratios. Due to the printer build volume, slight alterations were conducted for buildability and extrudability testing. Also, due to the low shear strength of materials, a shear vane device was modified for workability testing. Printing with sustainable materials, like dredged material, can significantly reduce the construction cost. General construction will benefit from controlled printing of cementitious materials with no longer a requirement for form work, which is 60-75% of the cost. The research concluded with the fabrication of panels to create shell structures using the mixtures with optimal performances in these tests.