Date of Graduation
12-2024
Document Type
Thesis
Degree Name
Master of Science in Civil Engineering (MSCE)
Degree Level
Graduate
Department
Civil Engineering
Advisor/Mentor
Barry, Michelle L.
Committee Member
Murray, Cameron D.
Second Committee Member
Hale, W. Micah
Keywords
3D Concrete Printing; Additive Construction; Civil Engineering
Abstract
This research focuses on the design and development of indigenous materials for Additive Construction (AC) mixtures. AC uses 3D printing techniques to extrude concrete layer-by-layer from a digital model to create 3D printed objects. In construction, AC can improve efficiency, speed, and sustainability, particularly in remote or resource-constrained environments and significantly reduce logistical demands and environmental impacts associated with traditional material transport. Key research objectives include identifying suitable additives for achieving printable soil-based mixtures and establishing practical, field-appropriate methods for assessing fresh properties that indicate printability. The findings highlight factors such as water content, cement content, additive type, and quantity and type of fines (i.e., particles smaller than 0.075 mm) affect a mix’s printability. Fines tended to improve the printability of a mix; however, they did cause a reduction in the compressive strength. The flow table test in combination with the hand squeeze test were shown to be simple, field-ready methods that could assess the pumpability of a mix. The values targeted did depend on the type of mix and the equipment used.
A small batch flow chart was also developed to guide decisions regarding printability, incorporating flowability ranges and compressive strength data for different custom mixes. Future research will focus on refining mix designs, exploring new material combinations, and evaluating scalability to enhance guidelines for testing methods and acceptance thresholds for printability.
Citation
Downing, B. (2024). Indigenous Materials Mixtures and AC Parameters. Graduate Theses and Dissertations Retrieved from https://scholarworks.uark.edu/etd/5605
