2021 Volume 32 Pages 25-33
The concrete waste generated when dismantling concrete structures is used as a roadbed material. However, the elution amount of hexavalent chromium derived from cement clinker may increase due to the progress of carbonation during storage. Therefore, in this study, we evaluated the effectiveness of the use of ground granulated blast furnace slag as one of the measures to suppress the elution of hexavalent chromium by elution tests and X-ray absorption fine structure measurements. As a result, we confirmed the reduction of hexavalent chromium eluted from the hardened cement by the reducing substance contained in the ground granulated blast furnace slag as the hydration reaction proceeded. Furthermore, the reducing effect of ground granulated blast furnace slag was maintained for a long period of time compared with other reducing substances. From the above results, we confirmed that ground granulated blast furnace slag is effective as a measure against the elution of hexavalent chromium.