Analysis of Environmentally Friendly Concrete (Green Concrete) Using Coal Fly Ash as a Substitute Material for Portland Cement in Road Pavement

Abstract The development of technology in the field of construction, especially in concrete technology, is now becoming more rapid, which requires concrete materials that can adapt to the times. As well as for energy savings from normal concrete materials from a mixture of fine, coarse, cement and water can now be added to other materials. In this era, the use of cement for concrete making materials is very identical, therefore to reduce the use of cement, it is necessary to mix other materials. The research method that researchers use is the experimental-laboratory method by making test objects in the form of concrete cylinders with a size of 15x30 cm. Analysis of concrete testing using Fly Ash mixtures in this study there are several variations of fly ash mixtures, namely fly ash 50%, 60%, and 70%. In testing several Fly Ash mixtures produced a compressive strength value of 50% Fly Ash percentage and 2% Accelerator of 161.630 kg/cm2, 60% Fly Ash and 2% Accelerator of 154.189 kg/cm2, 70% Fly Ash and 2% Accelerator of 92.670 kg/cm2. In the results of this study with several variations of fly ash mixtures, the highest compressive strength value was obtained at a percentage of Fly Ash 50% and Accelerator 2%, which amounted to 161.630 kg/cm2 with the first variation test specimen sample at the age of 28 days of concrete.