Mechanical properties and microstructure of concrete using Umeanyar slate stone powder as a filler

• Main Authors: Astariani, Ni Kadek, Sudika, I. Gusti Made, Budiarta, I. Wayan Balik
• Format: Conference Proceeding
• Language: English
• Subjects: Aluminum oxide; Calcium carbonate; Compressive strength; Fillers; Mechanical properties; Mechanical tests; Microstructure; Silicon dioxide; Stone; Tensile strength; X-ray diffraction
• ISSN: 0094-243X; 1551-7616
• DOI: 10.1063/5.0204961

This study aims to utilize slate stone powder as a filler in normal concrete mixes. This slate stone powder comes from waste produced by the Umeanyar crush stone industry in Buleleng, Bali. The content of this slate stone powder consists of SiO2 (49%), Al2O3 (11%), and CaO (11.2%). A cylinder was the test object used in this study with a size of 150x300 mm with variations in the addition of a filler of 0%, 2.5%, 5%, 7.5%, and 10%. The concrete mechanical tests shall be performed at compressive and split tensile strength, while microstructural tests are carried out by XRD (X-Ray Diffraction) and SEM-EDX (Scanning Electronic Microscope-Energy Dispersive X-Ray) tests. Compressive strength and maximum split tensile strength both increased with the addition of 2.5% filler, respectively 32.84 MPa and 7.93 MPa at 28 days of age. The presence of SiO2 and CaCO3 compounds, Fe2O3 compounds appear at the diffraction peaks resulting from the XRD test results. There was an increase in the element silica (Si) in the concrete with filler (A2.5%), and besides that, the element Fe also increased in the sample due to the addition of USPP filler.