İnce Taneli Zeminlerin Geoteknik Özelliklerinde Kalsine Edilmiş Fosfojips’in Etkisi

Bu çalışma, bir yapı malzemesi olarak ince taneli zeminlerin geoteknik özelliklerini yükseltmek için fosfojips gibi atık maddelerin kullanımını değerlendirmektedir. Kalsine Fosfojips (CPG) ile stabilize edilen zemin numuneleri üzerinde, standart proctor deneyi, Kaliforniya taşıma gücü ve serbest basınç ve optmum su muhevası deneyleri yapılmıştır. Gübre fabrikası atığı olan fosfojips 150 ºC gibi düşük sıcaklıkta kalsine edilmiştir. Kalsine edilmiş fosfojips (CPG) katılan ince taneli zeminlerin maksimum kuru yoğunluğu azalmıştır, ancak optimum su muhtevası değerleri artmıştır. Serbest basınç mukavemetinin, California taşıma gücü oranının, doğal ve stabilize zemin örnekleri üzerindeki etkileri araştırılmıştır. Deney sonuçları, stabilize edilmemiş numunelere kıyasla CPG katkılı karışımların daha yüksek dayanıklılığa sahip olduğunu göstermektedir. Sonuç olarak, CPG katkılı karışımların, yol inşaatları ve hafriyat dolgu uygulamaları için ince taneli zeminlerin dış etkilere karşı mukavemetinde başarılı bir şekilde kullanılabilineceği sonucuna varılmıştır. Test sonuçları, CPG içeren stabilize ince taneli zemin numunelerinin, doğal ince taneli zemin numunelerine kıyasla daha yüksek CBR direnci ve serbest basınç mukavemeti sergilediğini göstermektedir.

Effects of Calcined Phosphogypsum on the Geotechnical Parameters of Fine-Grained Soils

In this article, the using of waste materials has been studied such as phosphogypsum in the alteration of fine-grained soils in order to upgrade the geotechnical properties as a construction material. Standard Proctor test, unconfined compressive strength tests and California bearing ratio were carried out on Calcined Phosphogypsum (CPG) stabilized soil samples. It was determined that the phosphogypsum with additives calcined at the low temperature 150 ºC. Treatment with CPG generally reduces the maximum dry density but CPG increase the optimum moisture content. Compressive strength, California bearing ratio were performed to investigate effects of additive mixtures of stabilized and natural soil specimen. The empirical results show that stabilized samples with CPG additive mixtures have high durability as compared to unstabilized samples. These contribution blends have also improved the dynamic behaviors of the soil samples. As a result, we conclude that CPG additive mixtures can be completely used as an additive material to strength of granular soils in highway constructions and embankment applications. The experiment results understood that the stabilized fine-grained soil specimens containing CPG show high resistance to the CBR and unconfined compressive strengths as compared to natural fine-grained soil samples.

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Degirmenci N., Okucu A. and Turabi Ayse., Application of phosphogypsum in soil stabilization, Building and Environment, 42 (2007) 3393–3398.
Singh M., Influence of blended gypsum on the properties of Portland cement and Portland slag cement, Cement and Concrete Research, 30 (2000) 1185–8.
Altun IA. and Sert Y., Utilization of weathered phosphogypsum as set retarder in Portland cement, Cement and Concrete Research, 34 (2004) 677–80.
Singh M., Treating waste phosphogypsum for cement and plaster manufacture, Cement and Concrete Research, 32 (2002) 1033–8.
Kumar S., A perspective study on the fly ash-lime-gypsum bricks and hollow blocks for cost housing development, Construction and Building Materials, 16 (2002) 519–25.
Kumar S., Fly ash–lime–phosphogypsum hollow blocks for walls and partitions, Building and Environment, 38 (2003) 291–5.
Singh M. and Garg M., Cementitious binder from fly ash and other industrial wastes. Cement and Concrete Research, 29 (1999) 309–14.
Verbeek CJR. and du Plessis BJGW., Density and flexural strength of phosphogypsum-polymer composites, Construction and Building Materials, 19 (2005) 265–74.
Gregory CA., Saylak D. and Ledbetter WB., The use by-product of phosphogypsum for road bases and subbases, Transportation Research Board, Washington, DC, (1984) 998.
Chang WF., A demonstration project: roller compacted concrete utilizing phosphogypsum, Florida Institute for Phosphate Research Bartow, FL., 01 (1988) 068-072
Kolias S., Kasselouri-Rigopoulou V. and Kaarhalios., A., Stabilization of clayey soils with high calcium fly ash and cement, Cement and Concrete Composites, 27 (2005) 301–13.
Roy A., Kalvakoalve R. and Seals RK., Microstructure and phase characteristics of phosphogypsum cement mixtures, Journal of Materials in Civil Engineering, 8 (1998), 11-18.
ASTM C 150., Standard specification for Portland cement, Annual book of ASTM, Philadelphia, USA: The American Society for Testing and Materials, 04.01-04.02 (2002) 01-02
Rahman AMD., Lateric soil in construction, Building and Environment, 21 (1986) 57–61.
Pericleous MI. and Metcalf JB., Resilient modulus of cement-stabilized phosphogypsum, The Journal of Materials of Civil Engineering, 8 (1996) 7-10.
Federal Highway Administration., User guidelines for waste and byproduct materials, FHWA-RD-97-148, Washington DC. (1997).
Chen, F.H., Foundations on Expansive Soils. Elsevier, (1988).
Steinberg, M., Geomembranes and the Control of Expansive Soils in Construction. McGray-Hill, New York, (1998)
Nelson, J.D., Miller, D.J., Expansive Soils: Problems and Practice in Foundation and Pavement Engineering. John Wiley and Sons, Inc., New York, (1992).
Yong, R.N., Ouhadi, V.R., Experimental study on instability of bases on natural and lime/cement-stabilized clayey soils, Applied Clay Science,35 (2007) 238–249.
Puppala, A.J. and Musenda, C., Effects of fiber reinforcement on strength and volüme change in expansive soils, Transportation Research Record,00-716 (2002) 134–140
Akbulut, S., Arasan, S. and Kalkan, E., Modification of clayey soils using scrap tire rubber and synthetic fibers, Applied Clay Science, 38 (2007) 23–32.
Moavenian, M.H. and Yasrobi, S.S., Volume change behavior of compacted clay due to organic liquids as permeant, Applied Clay Science, 39 (2008) 60–71.
Degirmenci, N., The using of waste phosphogypsum and natural gypsum in adobe stabilization, Constr. Build. Mater., 22 (2008) 1220-1224.