Farklı yöntemlerle sıkıştırılmış betonların petrografisinin görüntü analizi yöntemi ile incelenmesi
For Roller compacted concretes (RCC) various compaction equipment and processes were studied in the literature; however, a compromise could not have been reached to determine the optimum methodology. The most common compaction methods can be listed as: vibrating table, vibrating hammer, modified proctor and superpave gyratory compactor. In the current study, to investigate the effects of different compaction methods on the physical properties, mechanical performance, and void structure, RCC mixtures consisting of different cement dosage, water content, and aggregate gradation were produced with these four compaction methods. In order to determine the performance of RCC mixtures under real field conditions, basic properties such as permeable pore voids volume, water absorption capacity, density in the hardened state, compressive strength, and splitting tensile strength were investigated. The void characterization of RCC mixtures with different compositions produced using different equipment and techniques was investigated in detail at the microstructural level. As the main objective of the thesis study, to determine the relationship between the void characterization of RCC mixtures and parameters such as cement dosage, water content, aggregate size, and compaction method, void contents of mixtures were characterized via a high-power petrographic microscope with 12x magnification capacity. To determine the characteristics of voids and to measure the amount of voids, the microscope images of a large number of thin-section samples with 50x60 mm dimensions taken from the RCC mixtures with a 1.25x0.04 mm lens were analyzed via image-analysis software. Considering all the parameters for the produced RCC mixtures, the samples produced with the gyratory compactor method showed the best performance in terms of compactibility. The Superpave gyratory compactor, which is less common than other methods, has been considered to be the most successful method for reflecting the field conditions during the gyration process. However, for the gyration compactor, the increase in gyration energy increased the compressibility in the first stage, while the result did not change much when the gyration number is 75 compared to 60 gyrations. While the vibrating hammer and the modified proctor had the best performances after the gyration compactor, it was observed that the vibrating table showed poor performances in terms of compactibility, especially at low water contents.