Kum-Bentonit Karışımlarının Hacimsel Deformasyon ve Yüksek Sıcaklık Altındaki Kayma Dayanımı Davranışının Perlit Katkısı Varlığında İncelenmesi

Enerji yapıları etrafında ortaya çıkan yüksek sıcaklığın zeminlerin mühendislik özelliklerini negatif yönde etkilemesi istenilmeyen bir durum olduğundan, bu alanlarda kullanılmak üzere yüksek sıcaklığa karşı bariyer görevi görecek yeni malzemelere ya da karışımlara ihtiyaç duyulmaktadır. Bu gereksinim doğrultusunda, inşaat sektöründe ısı yalıtımında kullanılan "perlit", halihazırda tampon malzeme olarak kullanılan kum-bentonit karışımına eklenerek yüksek sıcaklığa dayanıklı yeni bir karışım elde edilmesi amaçlanmıştır. Bu çalışmada perlit katkılı kum-bentonit karışımlarının oda sıcaklığı altında kompaksiyon, konsolidasyon deneyleri ve aynı zamanda hem oda (22~25°C) hem de yüksek sıcaklık altında (80°C) kesme kutusu deneyleri gerçekleştirilmiştir. Kompaksiyon deneylerinden elde edilen sonuçlara göre perlit katkısı kum-bentonit karışımlarının birim hacim ağırlık değerini azaltırken, optimum su içeriğini arttırmıştır. Karışımda perlit içeriği arttıkça toplam düşey deformasyonun arttığı ve kayma dayanımının hem oda hem de 80°C' sıcaklık altında perlit katkısı ile birlikte azaldığı belirlenmiştir.

Anahtar Kelimeler:

Kayma Dayanımı, Konsolidasyon, Kum-bentonit, Perlit, Yüksek Sıcaklık

Investigation of Volumetric Deformation and Shear Strength Behavior of Sand-Bentonite Mixtures under High Temperature in the Presence of Perlite Additive

High temperature that occurs around energy structures and facilities affects the engineering behavior of soils. For that reason new materials or mixtures that will act as a barrier which resist to high temperatures are needed. In line with this requirement, "perlite", which is frequently used in thermal insulation in the construction industry, was added to the sand-bentonite mixture, which is currently used as a buffer material, to obtain a new mixture that is durable under high temperatures. In this study, compaction and consolidation tests of perlite-added sand-bentonite mixtures at room temperature, as well as direct shear tests at both room and high temperature (80°C) were conducted. As a result of the compaction test results, it was observed that the perlite additive decreased the dry unit weight of the sand-bentonite mixtures, while the optimum water content increased. It was determined that as the perlite content in the mixture increased, the total vertical deformation increased and the shear strength decreased with the addition of perlite both at room and at 80°C.

Keywords:

Shear Strength, Consolidation, Sand-bentonite, Perlite, High Temperature,

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