Scopus İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/395
Browse
2 results
Search Results
Article Citation - WoS: 33Citation - Scopus: 32Unconfined Compressive Strength and Freeze-Thaw Resistance of Sand Modified With Sludge Ash and Polypropylene Fiber(Techno-press, 2017) Gullu, Hamza; Fedakar, Halil I.In recent years, the amount of sludge ash (SA) has considerably increased due to rapid urbanization and population growth. In addition, its storage in landfills induces environmental pollution and health problems. Therefore, its disposal in an environmentally friendly way has become more important. The main goal of this study is to investigate the reusability of sludge ash as an additive with polypropylene fiber (PF) to stabilize marginal sand based on the compressive strength performances from UCS tests. For this purpose, a series of UCS tests was conducted. Throughout the experimental study, the used inclusion rates were 10, 15, 20 and 30% for sludge ash and 0, 0.5 and 1% for polypropylene fiber by total dry weight of the sand+sludge ash mixture and the prepared samples were cured for 7 and 14 days prior to the testing. Freezing and thawing resistance of the mixture including 10% sludge ash and 0, 0.5 and 1% polypropylene fiber was also examined. On the basis of UCS testing results, it is said that sludge ash inclusion remarkably enhances UCS performance of sand. Moreover, the addition of polypropylene fiber to the admixtures including sand and sludge ash significantly improves their stress-strain characteristics and post-peak strength loss as well as UCS. As a result of this paper, it is suggested that sludge ash be successfully reused with polypropylene fiber for stabilizing sand in soil stabilization applications. It is also believed that the findings of this study will contribute to some environmental concerns such as the disposal problem of sludge ash, recycling, sustainability, environmental pollution, etc. as well as the cost of an engineering project.Article Citation - WoS: 1Effect of Mineralogical Composition of Clinoptilolite-Bearing Tuffs on Their Performance as a Natural Pozzolan in Cementitious Systems(Techno-press, 2021) Ozen, Sevgi; Uzal, BurakIn this study, pozzolanic reactivity and strength activity of zeolitic tuffs containing similar amount of zeolitic phase (clinoptilolite) and different types and amounts of impurities were examined in order to understand the role of mineralogical composition in the efficiency of zeolitic natural pozzolans. Mineralogical and chemical compositions as well as the physical properties of the zeolitic tuffs were determined. Their pozzolanic reactivity were measured as depletion of calcium hydroxide in the pastes containing lime and zeolitic tuff, which is determined by thermogravimetric analysis. Furthermore, compressive strength of blended cement mortars prepared with 20% replacement of Portland cement by finely ground tuffs were determined at 7, 28 and 56 days of age. It was demonstrated that the type and amount of impurities in mineralogical composition of zeolitic tuffs are significantly effective on their early pozzolanic reactivity. Zeolite mineral content, however, is more determinative on long term reactivity. For a strength activity, mineralogical composition was clearly effective on the preparation of mortar samples, which depends on water requirement of zeolitic tuffs.