Mechanical properties of 3D printed material with binder jet technology and potential applications of additive manufacturing in seismic testing of structures

Abstract

Additive manufacturing can be used for the construction of small-scale specimens that are useful for the understanding of the seismic behavior of conventionally constructed masonry structures. In fact, it can provide useful information for the validation of the global level assumptions that numerical models of structures have to make, but are hard to validate as large-scale tests are very expensive. To this end, this paper suggests the use of a Binder Jet printer to manufacture small-scale masonry models. The first step for such a validation procedure is the determination of the mechanical properties of the bulk material printed with a Binder Jet printer. Compression and bending tests on a sand based printer that uses furan binder shows that the bulk material presents anisotropy in compression, but to a lesser degree than other powder based printers. In tension, the anisotropy is found to be statistically insignificant – in stark contrast with values reported in the literature for powder based printers. Aging is found to be crucial for the mechanical properties: They are found to reach a plateau after 15 days of curing time. No scale phenomena were observed for length scales between 50 and 100 mm.