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In emerging countries, the driving elements for sustainable development are greenhouse and global warming concerns and the need for the development of low-CO 2 cements as replacement for Portland cement. Pumice is an aluminosilicate-type material that can be condensed with NaOH and Na 2 SiO 3 solution and can be used for green building with reduction in CO 2 footprint. The present paper highlights the effect of curing temperature on Hasankale pumice activation. Four curing temperatures have been investigated in this paper, 25°C, 45°C, 65°C, and 85°C, and 65°C has been confirmed as the best temperature for ground pumice activation. Furthermore, the aging effect has been studied at different curing temperatures. The aging of the samples before 28 days has a remarkable effect on compressive strength gain, but after 28 days this effect is inconsiderable for all heat treatment temperatures.

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Aluminosilicate type materials can be activated in alkaline environment and can produce geopolymer cements with low environmental impacts. Geopolymers are believed to provide good fire resistance so the effects of elevated temperatures on mechanical and microstructural properties of pumice based geopolymer were investigated in this study. Pumice based geopolymer was exposed to elevated temperatures of 100, 200, 300, 400, 500, 600, 700 and 800°C for 3 h. The residual strength of these specimens were determined after cooling at room temperature as well as ultrasonic pulse velocity, and the density of pumice based geopolymer pastes before and after exposing to high temperature was determined. Microstructures of these samples were investigated by Fourier transform infrared for all temperatures and SEM analyses for samples that were exposed to 200, 400, 600 and 800°C. Specimens, which were initially grey, turned whitish accompanied by the appearance of cracks as temperatures increased to 600 and 800°C. Consequently, compressive strength losses in geopolymer paste were increased with increasing temperature level. On the other hand, compressive strength of geopolymer paste was less affected by high temperature in comparison with the ordinary Portland cement. As a result of this study, it is concluded that pumice based geopolymer is useful in compressive strength losses exposed to elevated temperatures.

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ABSTRACT:The analyses of infill frame structures are generally done ignoring the presence of brick masonry in the analytical models but it is a prevalent mistake. Behaviors of such buildings vary significantly during the earthquake events. The lateral resisting capacity of infill wall actually restricts the column only up to the wall height but above the wall height, the free column deforms easily. In this paper, the effect of infill wall in formation of short column at military aid watchtower in Turkey has been analyzed and the analysis result compared with effect of earthquake that have been seen after earthquake. Keywords: RC structures, Masonry infill walls, Short column, EarthquakeBetonarme Binalarda Kısa Kolon Oluşumunda Dolgu Duvar Etkisi: Örnek Çalışma ÖZET: Dolgu duvar çerçeve yapılarının analizleri genellikle analitik modellerde tuğla duvar varlığını dikkate alınmadan yapılır fakat bu yaygın bir hatadır. Bu tür binaların davranışlar deprem durumunda önemli ölçüde değişmektedir. Dolgu duvarın yanal kuvvetlere dayanım kapasitesi gerçekte kolonu duvar yüksekliğine kadar olan bölümde sınırlamaktadır, duvar yüksekliğinin üstünde kalan kolon kolayca deforme olmaktadır. Bu çalışmada, Türkiye'de askeri bir karakol gözetleme kulesinde depremden dolayı oluşan kısa kolonda, dolgu duvar etkisi analiz edilmiş ve analiz sonucu deprem öncesi durumla karşılaştırılmıştır.