KUM / GEOTEKSTGL ARAYÜZEY KAYMA DAYANIMININ KESME KUTUSU DENEYLERGȱGLE BELGRLENMESG

Geoteknik mühendisliği alanında geosentetik malzemelerin kullanımına günümüzde oldukça yaygın bir şekilde rastlanmaktadır. Geoteknik uygulamalarda geosentetikler ayırma, filtrasyon, drenaj, güçlendirme işlevlerinden biri esas olmak üzere birçok işlevi bir arada yerine getirirler. Yüksek çekme dayanımına sahip bir geosentetik malzeme olan geotekstiller zeminin kayma mukavemetinde iyileşmeye neden olarak zemini güçlendirme görevini görürler, bu nedenle geotekstillerle güçlendirilmiş zeminler donatılı zemin olarak da adlandırılırlar. Özellikle yol inşaatlarında stabiliteyi artırmada ve temel altı tabakasını güçlendirmede kullanılan geosentetik malzemelerinin zeminin mekanik özelliklerini ne ölçüde iyileştirdiği birçok çalışmanın konusu olmuştur. Bu çalışma kapsamında, kumlu zeminlerde geotekstil kullanımının statik yükleme koşulları altında zeminin stabilitesindeki artış miktarına etkisi incelenmiştir. Bu amaçla bir seri kesme kutusu deneyi yapılmıştır. Deneysel çalışmalarda farklı tip ve özelliklerdeki geotekstiller kullanılarak kumların kayma direnci özelliklerinin ne ölçüde değiştiği araştırılmıştır.Deney sonuçları, geotekstil tipi, kum zeminin granülometrisi ve relatif sıkılığı ile deneysel koşullardaki farklılıkların ara yüzey kayma dayanımı parametreleri üzerinde büyük ölçüde etkili olduğunu ortaya koymuştur.

Anahtar Kelimeler:

Kum, geotekstil, kesme kutusu deneyi, ara yüzey sürtünme açısı, ara yüzey etkileşim katsayısı

Determination of Sand / Geotextile Interface Shear Strength by Direct Shear Tests

Recently, in geotechnical engineering field, applications of geosynthetics are gettingrather more common. Geosynthetics are capable of overcoming a number of problems includingseperation, filtration, drainage, reinforcement; which multiple functions can be fulfilled once at atime. Particularly, application of a type of geosynthetics, namely, geotextiles, which are possessingrather high tensile strength, lead to increase in the shear strength of soil, hence, soils strengthenedwith geosythetics are named as reinforced soil.In particular, many studies in the literature are related with the investigation of the rate ofincrease in soil strength by application of geosynthetic materials, which are used for increasing thestability and reinforcing the subgrade material in highway construction. In the scope of this study,the effect of geotextile type on the rate of increase in stability of sandy soils, is investigated understatic loading conditions. Shear box tests on specimens prepared by inclusion of geotextiles ofdifferent types and properties, were carried out to assess the rate of variation in sand shear strengthproperties. It was observed that geotextile type, grain size distribution, relative density of sand andthe test parameters cause drastic variations in the sand / geotextile interface shear strength behaviour.

Keywords:

Sand, geotextiles, direct shear test, interface friction angle, interface coefficient of friction,

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