Abstract
The availability of used roofing tiles as fine aggregate for concrete was evaluated in terms of compressive strength. Roofing tile scrap with a diameter of less than 5 mm was mixed as fine aggregate for fresh concrete as a substitution for sand. After 28 days of aging, the compressive strength of the sample pieces of concrete was measured under JIS A1108. According to the experimental results, the cement/water ratio highly influenced the compressive strength of the concrete, indicating that the water content of the roofing tile aggregate should be controlled. We propose the Time Domain Reflectometry (TDR) method for measuring the water content of roofing tile scrap as an expeditious method on site. Our proposed method enables the production of concrete mixed with roofing tile scrap with higher compressive strength than ordinary concrete without roofing tile scrap.
