Development of Structural Capacity Relations for 3D Printed Lightweight Concrete with Mixtures Including Expanded Polystyrene
Restricted (Penn State Only)
- Author:
- Aminpour, Nima
- Graduate Program:
- Architectural Engineering
- Degree:
- Doctor of Philosophy
- Document Type:
- Dissertation
- Date of Defense:
- June 07, 2024
- Committee Members:
- Julian Wang, Professor in Charge/Director of Graduate Studies
Jose Pinto Duarte, Outside Field Member
Nathan Brown, Major Field Member
Ali Memari, Chair & Dissertation Advisor
Aleksandra Radli¿ska, Outside Unit Member - Keywords:
- 3D concrete printing
structural analysis
concrete
atoumated construction - Abstract:
- This study focuses on developing a structural capacity determination procedure for 3D Concrete Printing (3DCP) with a mixture design including Expanded Polystyrene (EPS), which yields a Light-Weight Concrete (LWC), through experimental, analytical, and numerical methods. The concrete mixtures used in this study, consisting of cementitious material, sand, and EPS, introduce new behavior in concrete by significantly increasing plastic strain while reducing weight. The application of EPS concrete is analyzed in both as a printed section and infill material for 3DCP walls. The structural evaluation study begins with determination of mechanical properties through appropriate tests on small-scale 3DCP elements, followed by calibration of Finite Element Analysis (FEA) in Abaqus. These experiments were conducted on both the developed LWC and the conventional normal-weight concrete (NWC), with time intervals between layers to assess the effect of cold joints on 3DCP. The research then progressed to experimental tests for out-of-plane flexure on 3DCP walls with cells filled with LWC containing EPS. The results indicated the significant contribution of the printed shell to the flexural resistance of the section, with acceptable strength compared to fully cast concrete walls. FEA analysis was conducted on the walls, and the results were compared to assess the model. Finally, experimental test results were used to analyze a complete 3DCP building in three states, with loads obtained from ASCE 7-16, to compare the adequacy of 3DCP materials in different regions. The results indicated that 3DCP can be modeled using both macro-modeling and micro-modeling approaches, both of which showed a good correlation with experimental results. Furthermore, the results indicated that the strength of 3DCP filled with concrete is lower than that of normal cast concrete.