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

Year 2024, , 585 - 594, 26.09.2024

Metin Davraz , Şemsettin Kılınçarslan , Murat Koru

https://doi.org/10.21923/jesd.1178373

Abstract

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.

Keywords

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

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

Abstract

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.

Keywords

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

References

• Aldridge D., Ansell T. (2001) Foamed concrete: production and equipment design, properties, applications and potential. In: Proceedings of one-day seminar on foamed concrete: properties, applications and latest technological developments. Loughborough University.
• Durack, J. M., Weiqing, L., (1998) The properties of foamed air cured fly ash-based concrete for masonry production. In Proceedings of the Fifth Australasian Masonry Conference (pp. 129-38). Gladstone The Queensland, Australia.
• Hunaiti, Y. M., (1997) Strength of composite sections with foamed and lightweight aggregate concrete. Journal of materials in civil engineering, 9 (2), 58-61. https://doi.org/10.1061/(ASCE)0899-1561(1997)9:2(58).
• Goltas Cement Inc. Monthly Cement Analysis Report, August 2020.
• Jeong, J. Y., Kim, J. M., (2011) Properties of low density foamed concrete for building construction using anionic surfactants of synthetic and natural materials. Journal of the Korea Institute of Building Construction, 11(6), 557-566. https://doi.org/10.5345/JKIBC.2011.11.6.557.
• Jones M.R., McCarthy A., (2005) Utilizing unprocessed low-lime coal ash in foamed concrete. Fuel. Vol.84, pp. 1398-1409. https://doi.org/10.1016/j.fuel.2004.09.030.
• Jones M.R., McCarthy A., (2005) Preliminary views on the potential of foamed concrete as a structural material. Magazine of concrete research, 57(1), 21-31. https://doi.org/10.1680/macr.2005.57.1.21.
• Just, A. and Middendorf B., (2009). Microstructure of high-strength foam concrete. Materials characterization, 60 (7), 741-748. https://doi.org/10.1016/j.matchar.2008.12.011.
• Kearsley, E. P., Wainwright, P. J., (2001). The effect of high fly ash content on the compressive strength of foamed concrete. Cement and concrete research, 31(1), 105-112. https://doi.org/10.1016/S0008-8846(00)00430-0.
• Kearsley, E. P., Wainwright, P. J., (2002). The effect of porosity on the strength of foamed concrete. Cement and concrete research, 32 (2), 233-239. https://doi.org/10.1016/S0008-8846(01)00665-2
• Kearsley E.P., Booyens P.J., (1998) Reinforced foamed concrete, can it be durable. Concrete Beton Vol. 91, pp. 5-9.
• Kılınçarslan, Ş., Tuzlak, F., (2018) Investigation of Strength and Thermal Conductivity Properties of Foam Concrete with Fly Ash. International Journal of Sustainable Engineering and Technology, 2(1), 1-5.
• McCormick, F. C., (1967). Rational proportioning of preformed foam cellular concrete. In Journal Proceedings (Vol. 64, No. 2, pp. 104-110).
• Nambiar, E. K., Ramamurthy, K., (2006). Models relating mixture composition to the density and strength of foam concrete using response surface methodology. Cement and Concrete Composites, 28 (9), 752-760. https://doi.org/10.1016/j.cemconcomp.2006.06.001.
• Nambiar, E. K., Ramamurthy, K. (2007). Sorption characteristics of foam concrete. Cement and concrete research, 37(9), 1341-1347. https://doi.org/10.1016/j.cemconres.2007.05.010.
• Ramamurthy, K., Nambiar, E. K., and Ranjani, G. I. S. (2009). A classification of studies on properties of foam concrete. Cement and concrete composites, 31(6), 388-396. https://doi.org/10.1016/j.cemconcomp.2009.04.006.
• Regan P.E., Arasteh A.R., (1990) Lightweight aggregate foamed concrete. Structural Engineer, Vol. 68 (9), 167-73.
• Rudnai G., (1963) Lightweight concretes. Budapest, Akademikiado, https://lib.ugent.be/catalog/rug01:001029927
• S. Van Deijk, (1991) Foam concrete, Concrete 25 (5).
• Short A., Kinniburgh W., (1963) Lightweight concrete. Asia Publishing House.
• London: Applied Science Publishers, 1978.
• Tam, C. T., Lim, T. Y., Sri Ravindrarajah, R., Lee, S. L., (1987). Relationship between strength and volumetric composition of moist-cured cellular concrete. Magazine of Concrete Research, 39 (138), 12-18. https://doi.org/10.1680/macr.1987.39.138.12
• Tikalsky P.J., Pospisil J., MacDonald W.A., (2004) Method for assessment of the freeze-thaw resistance of preformed foam cellular concrete. Cement and Concrete Research. 34(5), 889-893. https://doi.org/10.1016/j.cemconres.2003.11.005.
• TS EN 678, (1995) Determination of the Dry Density of Autocloved Aerated Concrete, Turkish Standard Institute, Ankara, Turkey.
• TS EN 1354, (2007) Determination of compressive strength of lightweight aggregate concrete with open structure, Turkish Standard Institute, Ankara, Turkey.
• TS EN 12390-6, (2009) Testing hardened concrete - Part 6: Tensile splitting strength of test specimens, Turkish Standard Institute, Ankara, Turkey.
• TS EN 12667, 2003. Thermal performance of building materials and products- Determination of thermal resistance by means of guarded hot plate and heat flow meter methods-Products of high and medium thermal resistance, Turkish Standard Institute, Ankara, Turkey.
• Valore, R. C., (1954) Cellular concretes Part 1 composition and methods of preparation. In Journal Proceedings (Vol. 50, No. 5, pp. 773-796).