INVESTIGATION OF THE EFFECTS OF DENSITY ON PHYSICAL, MECHANICAL AND THERMAL PROPERTIES OF FOAM CONCRETE

Öz

Foam concrete; It is a type of lightweight concrete that can be produced by adding cement, water, surfactant, and if desired, sand or fine aggregate. It has high fluidity in fresh form and low density after hardening. It can provide a thermal conductivity of 90 mW/mK at a density of 400 kg/m3. In this study, the foam concrete samples were produced by adding 80 g/L density foam to the mortars prepared at 300 kg/m3 cement dosage and 0.30 water/solid ratio using CEM I 42.5 R type Portland cement, limestone powder, polypropylene fiber, and superplasticizer additive. The compressive strength, split tensile strength and thermal conductivity properties of the samples produced in 12 different dry densities in the range of 300-1400 kg/m3 were tested. As the dry density values of the samples increased, the thermal conductivity and compressive strength values increased. Equations were proposed to estimate the compressive strength and thermal conductivity depending on the dry density of the foam concrete with limestone powder aggregate from the findings.

Anahtar Kelimeler

• Foam Concrete
• Dry Density
• Thermal Conductivity
• Compressive Strength
• Split Tensile Strength

YOĞUNLUĞUN KÖPÜK BETONUN FİZİKSEL, MEKANİK VE TERMAL ÖZELLİKLERİ ÜZERİNDEKİ ETKİLERİNİN ARAŞTIRILMASI

Öz

Köpük beton; çimento, su, sürfaktan ve istenirse kum ya da ince agrega ilave edilerek, ısıl işlemsiz olarak üretilebilen bir hafif beton türüdür. Taze halde yüksek akıcılığa ve sertleştikten sonra düşük yoğunluğa sahiptir. 400 kg/m3 yoğunlukta 90mW/mK ısıl iletkenlik katsayısını sağlayabilmektedir. Bu çalışmada CEM I 42.5 R tipi Portland çimentosu, kalker tozu, poliproplen elyaf ve süper akışkanlaştırıcı katkı maddesi kullanılarak, 300 kg/m3 çimento dozajı ve 0.30 su/katı oranında hazırlanan harçlara 80g/L yoğunlukta köpük ilavesiyle hafif beton numuneleri üretilmiştir. 300-1400 kg/m3 aralığında 12 farklı kuru yoğunlukta üretilen numunelerin (28. gün) basınç dayanımı, yarmada çekme dayanımı ve ısıl iletkenlik özellikleri test edilmiştir. Elde edilen bulgulardan kalker tozu agregalı köpük betonun kuru yoğunluğuna göre basınç dayanımı, yarmada çekme dayanımı ve ısıl iletkenlik katsayılarının değişimlerini tahmin etmeye yönelik bağıntılar önerilmiştir.

Anahtar Kelimeler

• Köpük Beton
• Kuru Yoğunluk
• Isıl İletkenlik Katsayısı
• Basınç Dayanımı
• Yarmada Çekme Dayanımı

Kaynakça

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