摘要: |
The research program will investigate the construction of fiber reinforced cementitious material (FRCM) components using extrusion-based 3D printing. Where conventionally formed concrete structures rely on the formwork for strength and stability during the hardening process, components constructed using 3D printing must rely on their green strength (i.e., strength during the time when the concrete has set but not appreciably hardened) and stiffness to resist instability, such as buckling and creep, during construction. As such, this proposal will investigate 3D printing from the point of view of materials and structural engineering, rather than construction. This study will result in engineered, 3D printed FRCMs meeting required quality control and engineering properties (from fresh to fully hardened) to simulate the response of the materials during construction (printing) and in their hardened state. The study is separated into the following research tasks to meet these specific objectives, as follows:
(1) Design and fabricate material extrusion-based 3D printer for construction of FRCM components; (2) Develop a quality control protocol to investigate voids and fiber alignment of 3D printed FRCM components using x-ray tomography; (3) Investigate fresh-state properties of FRCMs fabricated using 3D printing; (4) Investigate hardened engineering properties of FRCMs fabricated using 3D printing; and (5) Disseminate research findings to the construction and structural engineering communities through partnership with Lafarge and the City of Seattle. |