COMPUTATIONAL MODELING FOR STRUCTURAL ELEMENTS ANALYSIS USING CEMENT COMPOSITES IN 3D PRINTING
additive manufacturing; non-linear properties; numerical simulations; finite elements; cement composites.
The construction industry has been incorporating 3D printing as an innovative technology. However, there are still challenges involving the complexity of the necessary parameters, such as the geometric characteristics, strength, and rigidity of the printed objects. In this way, this study proposes a new tridimensional computational modeling for dimensioning 3D printed structures. The model is based on the physical non-linearity of the material and the geometric non-linearity of the structure. It consists of a numerical reproduction of an experimental test using finite elements and considers the material properties evolution over time through construction phases. The printing speed is 60 mm/s and the time interval between layers of 11s. Allied to this, an analytical model is also proposed to verify the failure type of the structural element - plastic collapse or buckling. The results obtained revealed good agreement with those from experimental tests and consolidated theoretical formulation, being the differences between computational and theoretical methods 0.58% to 3.38% for different building rates. In terms of vertical normal stress at the base of the walls, the maximum percentage variation between the models is of 5.22%, and in terms of vertical displacements, variations are smaller than 1 mm in absolute values. The computational model successfully predicted the failure moment of the structure, and the analytical model correctly revealed the type of failure. The parametric analyses showed that the proposed model is an accessible, effective, and accurate tool to reveal the effects of printing speed and material properties on the printing process.