Malzeme özelliklerinin ve yalıtım sisteminin isi köprüsü davranışına etkisinin incelenmesi

Öz

Enerji tüketiminin azaltılması ülkelerin gelişimi için çok önemlidir. Yapılarda enerji tüketimi bu nedenle büyük önem arz etmektedir. Binalarda ısı kaybını azaltmak için ısı köprülerini, ısı köprülerini oluşturan yalıtım sisteminin etkilerini ve kullanılan malzemenin davranışlarını çok iyi bilmek gerekmektedir. Bu çalışma, teras katlarda beton, duvar ve yalıtım malzemelerinin ısıl iletkenlik katsayılarının değişiminin ısı köprüsüne etkilerini incelenmektedir. Bunun için literatürden farklı olarak Türkiye'de betonarme binaların teras katları için en sık kullanılan 9 kesit üzerinde inceleme gerçekleştirilmiştir. "Yalıtım sistemi, beton ve/veya duvar malzemesinin değişiminin ısı köprüsüne etkisi ne olmaktadır?" sorusuna yanıt aranmıştır. Hesaplamalar TS 825’te belirtilen birinci derece gün bölgesi için sıvalı durum göz önünde bulundurularak yapılmış olup farklı yalıtım çeşitlerinde duvar-döşeme-kiriş birleşimlerinin ısı akıları ve sıcaklıkları hesaplanmıştır.  Hesaplamalarda gerçeğe yakın değerler veren ve sonlu elemanlar metodunu kullanan, QuickField 5.6 programından yararlanılmıştır. Bu çalışmanın sonuçları ile ısı köprülerinde beton, duvar ve yalıtım malzemelerinin ısıl iletkenlik değerlerinin değişiminin iki boyutlu olarak nasıl değiştiği görülmektedir. En büyük ısı kaybı, betonun ısıl iletkenlik katsayısının artması sonucunda elde edilmektedir. Ayrıca elde edilen sonuçlarla teras katlarda kullanılan yalıtım çeşitlerinin hangisinin daha verimli olduğu sorularına da yanıt verilmektedir.

Anahtar Kelimeler

• Isı köprüsü,Isıl iletkenlik,Isıl kayıp,Teras katlar

The effect of material properties and isolation system on thermal bridge behavior

Abstract

Reducing the energy consumption is very important for the development of the countries. For this reason, energy consumption at the buildings is very important. It is necessary to know behaviours of thermal bridges, affects at insulation system utilized and materials constituting the thermal bridges very well to cut down thermal loss in buildings, this study searches affects at change in the thermal conductivity coefficients of concrete, wall and insulation materials used in the terrace floors on the thermal bridges . For this reason, apart from literature, examination on 9 insulation sections most frequently used for the terrace floors at reinforced concrete buildings in Turkey were realized. What is the effect of changes at insulation system and/or the concrete and the wall materials on the thermal bridge?”. Answers to this question was  researched. Calculations were made for temperature and heat flux distributions at wall-floor-beam combinations at different insulation states considering  plastered state for first degree day area, as mentioned in TS825 Standard. For the calculations, QuickField 5.6 program, which gives realistic values and utilizes finite elements method was used.  With the results of this study, it was  seen how the behavior of the variance of the concrete, wall and insulation heat conductivity values at the thermal bridges changes in a two-dimensional way. As a result of the calculations, the biggest heat loss was obtained when thermal conductivity coefficient of the concrete increased. Besides, answers are given to  questions such as which is the most productive section  used in terrace floors?

Keywords

• Thermal bridges,Thermal conductivity,Thermal loss,Terrace floors

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