Extrusion Nozzle Shaping for Improved 3DP of Engineered Cementitious Composites(ECC/SHCC)

摘要

This paper focuses on the development of a nozzle steering and shaping system for concrete 3D printing(3DCP)of Engineered/Strain Hardening Cementitious Composites(ECC/SHCC).The investigation highlights the development of an integrated system that includes robotic end-effector tooling,automated control associated with the delivery and deposition processes,as weE as multi-axis nozzle steering for enhanced surface quality of the printed components.The results are discussed along with demonstrated prototypes.While significant improvements to the speed and efficiency of 3DP cementitious materials have been developed in recent years,only a few precedents,discussed in the paper,have aimed to improve geometric surface quality of the final printed components.In addition to improving the surface quality,the designed extrusion shaping process has the potential to improve mechanical performance of ECC by maximizing interfacial surface area and improving fiber alignment.Material effects will also be discussed in relation to the development of the overall system.An overview of the geometric capabilities and limitations of the proposed system will be presented in comparison with existing 3DP techniques.