2026-05-20T05:01:08Zhttps://keep.lib.asu.edu/oai/requestoai:keep.lib.asu.edu:node-2011462025-05-05T15:53:02Zoai_pmh:alloai_pmh:repo_items201146
https://hdl.handle.net/2286/R.2.N.201146
http://rightsstatements.org/vocab/InC/1.0/
All Rights Reserved
2025
348 pages
Doctoral Dissertation
Academic theses
en
Surehali, Sahil
Neithalath, Narayanan
Mobasher, Barzin
Azeredo, Bruno
Hoover, Christian
Yellavajjala, Ravi
Rajan, Subramaniam
Arizona State University
Partial requirement for: Ph.D., Arizona State University, 2025
Field of study: Civil, Environmental and Sustainable Engineering
The increasing adoption of 3D concrete printing (3DCP) in construction presents challenges related to anisotropy, interfacial bonding, and material performance. This dissertation provides a comprehensive investigation into the mechanical, durability, and rheological properties of 3D printed concrete, while also exploring the potential of novel graphene-based nanomaterials—fractal graphene (FG) and reactive graphene (RG)—to enhance performance. The research is divided into two major sections: (i) understanding the influence of print parameters on mechanical and transport properties, and (ii) evaluating the role of graphene towards developing high-performance cement-based composited for 3DCP.This study systematically quantifies the effects of print layer height and test direction on the anisotropic compressive behavior of printed elements, revealing that inter-layer interfaces are key weak points contributing to directional dependency in strength. The research also examines the influence of layer height on chloride transport, demonstrating that higher layer heights reduce interfacial defects but increase bulk porosity, affecting durability. To address these challenges, the study explores the use of FG and RG as nano-additives to improve 3D printed concrete’s properties. These novel graphene types, produced via a scalable and environmentally friendly detonation synthesis, enhance cement hydration, refine pore structures, and improve mechanical strength even at ultra-low dosages. Rheological analysis reveals that FG and RG significantly enhance yield stress, viscosity, and thixotropy, with RG demonstrating superior performance due to its functionalized surface groups. A novel oscillatory rheology-based approach is introduced to assess early-age structuration, providing a predictive framework for material delivery, extrusion stability, and buildability in 3DCP. Experimental results show that graphene-enhanced mixtures double achievable print heights and improve layer stability, offering a cost-effective solution for enhancing 3DCP. A comparative life cycle analysis of FG- and RG-modified mortars indicates up to 15% reductions in global warming potential and energy demand compared to conventional mortars, highlighting the environmental benefits of graphene-enhanced cementitious materials. These findings demonstrate the feasibility of integrating nanomaterials in 3DCP to achieve high-performance, durable, and sustainable printed structures. These contributions provide a framework for improving the mechanical and durability properties of 3D printed concrete, facilitating its large-scale adoption in the construction industry while advancing sustainable building solutions.
Civil Engineering
Properties of 3D Printed Concretes and Evaluation of Novel Nanoscale Inclusions for their Enhancement