Title:
Early Age Response of 3D Printed Systems Evaluated Using Digital Image Correlation
Author(s):
Nair
Publication:
Web Session
Volume:
ws_S22_Nair.pdf
Issue:
Appears on pages(s):
Keywords:
DOI:
Date:
3/28/2022
Abstract:
This paper discusses the use of digital image correlation (DIC) to assess the buildability of 3D printed concrete wall elements as a function of time after mixing. DIC is used to track the displacement/strain profiles (with respect to time since start of printing) of four of the bottommost layers to predict the initiation of failure. It is shown that this approach helps determine a failure initiation height corresponding to the plastic deformation of the printed structure before visible collapse of the structure occurs. The critical (visible) failure heights are observed to be similar to or higher than the initiation heights and the difference depends on the mixture characteristics and the time since mixing (or property development). Average vertical strains and strain build-up rates are also used to infer time-dependent buildability of the mixtures. The strain build-up rates measured using DIC are inversely related to the stiffness development. The proposed approach, the fundamentals of which are provided here, can be used to evaluate the buildability of fresh 3D printed mortars and to dynamically adjust print paths to enhance buildability.