Selecting the Appropriate Quality Control Method for 3D Concrete Printing: A First Guideline

Presented By: Atta Rehman, Yonsei University The aim of this study is to evaluate the suitability of ten different test methods as potential quality control (QC) tests for testing and characterizing mono-component concrete used for 3D concrete printing (3DCP). Among evaluated tests, eight are offline tests (hand vane, rotational rheometer, uniaxial unconfined compressive strength, squeeze flow, slow penetration test, ultrasonic pulse velocity, slump, and flow table) and two are inline test methods (slug test and torque measurement of the pumping motor). Based on the results obtained from the offline methods, this study introduces a simple framework consisting of a nomogram that provides a comprehensive overview of the structural build-up and can be used for quality control assurance. This research proposes a novel concept of a "performance index" that measures a test method's ability to detect evolution in rheological properties accurately. The study establishes a ranking of the offline test methods based on the proposed performance index. Furthermore, this study evaluates the practical aspects of using the different test methods, such as portability, cost, required labor, and material, to determine their effectiveness as QC test instruments. Researchers and practitioners can use the findings as a first guideline to choose an appropriate QC technique.