3D Printing of a Cement-Based Mortar in a Complex Fluid Suspension: Analytical Modeling and Experimental Tests

Assessing the fresh properties of printable cement-based materials: High potential tests for quality control

“…Rotational rheometry has been intensively used in the recent past for assessing the so-called "structural build-up" of cement-based materials [37]. Predominantly, Constant Rotational Velocity (CRV) test, also referred to as Constant Shear Rate (CSR) test, was used for this purpose [18,[38][39][40][41]. In single CRV test, a low value of constant rotational velocity is applied to the material until flow onset occurs.…”

“…A large variety of applied rotational velocities or shear rates, which can differ by a couple orders of magnitude, are therefore reported in literature. For instance, while testing printable mortars with various devices and geometries, Perrot et al [18] applied a CSR of 0.001 s − 1 , Benamara et al [39] used 0.01 s − 1 , and Panda et al [38] performed flow onset measurements at 0.1 s − 1 . This range of rotational velocities is still today a very open research question.…”

“…To evaluate the structural build-up of printable materials over time, single-batch approach is commonly implemented, i.e. multiple flow onset measurements are successively conducted on the same sample [18,38,39]. This protocol is opposed to multi-batch approach, which implies the use of an individual sample for each age of the material [17].…”

Foundation Piles—A New Feature for Concrete 3D Printers

“…ApisCor presented the concept of printing a flat slab by laying concrete trails at the appropriate angle [ 25 ]. The articles [ 28 , 32 ] present a method, called Injection 3D Concrete Printing, which is based on the concept that a liquid building material is injected into a gel-type support material with specific rheological properties ( Figure 1 c). This ensures that the support material maintains the stable position of the construction material.…”

“…A completely different approach to mix design must be taken when printing in a support material [ 28 , 32 ], where it is important to protect the mix from the adsorption of its components by the absorbent support material by using viscosity modifying admixtures. Printing when using support materials based on the Particle Bed Fusion technique [ 59 , 60 , 61 ] involves injecting a binder into a specially prepared substrate.…”