Safa NAYIR, Ümit BAHADIR, Şakir ERDOĞDU, Vedat TOĞAN

Taşıyıcı hafif betonun enerji performansı açısından değerlendirilmesi: Bir örnek çalışma

Bu çalışmada, pomza agregası içeren taşıyıcı hafif beton üretilmesi ve taşıyıcı hafif betonun enerji performansı açısından değerlendirilmesi amaçlanmıştır. Hafif beton üretimlerinde uçucu kül ve metakaolin çimento ile ikame edilerek kullanılmıştır. Karşılaştırma yapmak amacıyla normal ağırlıklı geleneksel beton üretilmiştir. Üretilen betonların basınç dayanımı, birim hacim ağırlık ve ısı iletkenlik katsayıları ilgili standartlara uygun olarak belirlenmiştir. Üretilen hafif betonların birim hacim ağırlıkları 1880-1900 kg/m3 ve basınç dayanımları 20-27 MPa arasında değişmektedir. Betonların ısı iletkenlik katsayıları birim hacim ağırlıkları azaldıkça azalmış olduğu ve 0.54-1.0 W/mK arasında değerler aldığı görülmektedir. Üretilen betonların belirlenen özellikleri örnek bir vaka için enerji simülasyon yazılımı DesignBuilder programı vasıtasıyla birincil enerji tüketimi ihtiyaçlarını değerlendirmek için kullanılmıştır. Normal ağırlıklı betona kıyasla, taşıyıcı hafif beton kullanımı ile yıllık enerji ihtiyacında %15-%19 oranında bir azalma görülmüştür. Ayrıca, aylık ısıtma ve soğutma yükleri dikkate alındığında, taşıyıcı hafif betonların ısıtma enerjisi ihtiyacını önemli derecede azaltmış olduğu görülmüştür. Soğutma enerji ihtiyacı ise beton tipinden önemli derecede etkilenmemiştir.

Anahtar Kelimeler:

Taşıyıcı hafif beton, Enerji performansı, Isı iletkenlik, Birim hacim ağırlık

Evaluation of structural lightweight concrete in terms of energy performance: A case study

In this study, it is aimed to produce structural lightweight concrete (SLWC) containing pumice aggregate and to evaluate its contribution to energy performance. Fly ash and metakaolin were used as substitutes with cement in the production of lightweight concrete. It was also produced normal weight concrete (NWC) for comparison. The compressive strength, the unit weight and the coefficient of thermal conductivity of the concretes produced were determined in accordance with relevant standards. The unit weights of the lightweight concrete are in the range of 1880-1900 kg/m3 , and the compressive strengths are between 20-27 MPa. It was observed that the thermal conductivity coefficients of the SLWCs are ranging from 0.54 to 0.63 W/mK and they decrease as the unit weights decrease. The properties of the SLWCs determined are used in the energy simulation software DesignBuilder to assess the primary energy consumption for a case study. With the use of SLWCs, it can be seen that the annual energy requirement decreases by 15% to 19% compared to NWC. In addition, when monthly heating and cooling loads are analysed, it can be seen that the SLWCs reduces the heating energy requirement significantly. However, the cooling energy needs were not significantly affected due to the type of concrete produced.

Keywords:

Structural lightweight concrete, Energy performance, Thermal conductivity, Unit weight,

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