EFFECT OF ADDING EGGSHELL AND LIMESTONE POWDER COMBINED FLY ASH AS A PARTIAL CEMENT REPLACEMENT ON 3D CONCRETE PRINTING

• Main Author: Akbar, Fas'ul
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/87967
• Institution: Institut Teknologi Bandung

Construction waste is a significant environmental issue that continues to grow along with the rapid development of infrastructure. One innovative solution to mitigate the impact of this problem is the application of digital construction technology based on additive manufacturing using cementitious materials, known as 3D Concrete Printing. Ordinary Portland Cement (OPC) is the primary material used in additive manufacturing-based construction technology. However, the increasing use of OPC significantly contributes to greenhouse gas emissions, particularly carbon dioxide (CO?). Therefore, efforts are needed to utilize recycled waste as a Supplementary Cementitious Material (SCM) to reduce the use of conventional cement. Eggshell powder and limestone powder, combined with fly ash, will be used in this study. Eggshell and limestone powder will replace cement at proportions of 10% and 20%, while fly ash will be used at 10%. The fresh concrete properties tests conducted include the Flow Table Test, Vicat Needle Test, Direct Shear Test, and Uniaxial Unconfined Compression Test (UUCT), while the hardened concrete properties are assessed through mortar compressive strength tests using a Universal Testing Machine (UTM). The curing method involves submerging the specimens in water for 3, 7, and 28 days. Additionally, an analysis of printability properties will be carried out to determine the optimal mix design and evaluate the fresh and hardened concrete properties with the addition of eggshell and limestone powder combined with fly ash for use in 3D Concrete Printing. Experimental studies have proven that the addition of eggshell powder and the combination of fly ash reduce workability, which positively affects buildability. In