JEOTEKSTİL TABAKALARININ ÇAKIL-SİLT KARIŞIMLARININ TAŞIMA KAPASİ-TESİ ÜZERİNDEKİ ETKİLERİ

Yıl 2015, Cilt: 16 Sayı: 2, 61 - 69, 15.12.2015

Keramat Sadehgi Azar Rouzbeh Dabiri

Öz

Toprak stabilizasyonu önceden belirlenmiş hedeflere ulaşmak için toprağın fiziksel ve mühendislik bir dizi özelliklerini değiştirmek ve geliştirmek anlamına gelir. Birçok mühendislik uygulamalarında, jeotekstil kullanımı top-rak ıslahı için etkili bir yöntem olarak kabul edilir. Araştırma sonuçları, geosentetik alt zemin ve alt taban katmanları arasına yerleştirildiğinde, ince taneli zeminin dayanma kapasitesini artırmak ta olduğunu göstermektedir. Bu çalış-manın temel amacı, bir laboratuvar çalışma da jeotekstil tabakasının etkisi çakıl kapasitesine ve katmanların sayısını değerlendirmektir. %15 ila 30 oranında silt içeren çakıllar, Şebister şehrinin Till bölgesinden elde edilmiştir. Deneme-ler üç farklı (%90, 95 ve 100) göreceli yoğunlukta gerçekleştirilmiş ve jeotekstil tabakanın etkisi iki farklı konumda incelenmiştir. İlk pozisyonda, bir jeotekstil tabakası toprak numunesinin orta kısmında yerleştirilmiş ve ikinci ko-numda iki jeotekstil tabakası alternatif olarak toprak numunesine konulmuştur. Laboratuvar çalışmalarının sonuçları numunelere bir jeotekstil tabakası konulmasının taşıma kapasitesinin geliştirmesine yardımcı olduğunu göstermiştir. Meydana gelen artışlar, çakıl ve % 30 silt içeren çakılda gözlenmiştir. Ancak, toprak içine alternatif olarak iki jeoteks-til katmanı koyulması numunelerin taşıma kapasitesi ve direncini azaltmaktadır.

Anahtar Kelimeler

Çakıl, Silt, Kaliforniya Taşıma Oranı (CBR) Deneyi, Toprak Stabilizasyonu

THE EFFECTS OF GEOTEXTILE LAYERS ON BEARING CAPACITY OF GRAVEL-SILT MIXTURES

Öz

Soil stabilization methods to modifying and improving the physical and engineering features of the soil for achieving a set of previously determined goals. In many engineering applications, the use of geotextiles is regarded as an effective method for soil improvement. Research results indicate that, when geosynthetics placed between the subgrade and sub base layers, increase the bearing capacity in fine grain subgrades. The main pur-pose of the present study was evaluating a laboratory study of the effect of geotextile layer and its number of lay-ers on the bearing capacity of the gravel of Til region of Shabestar city, which includes 15 to 30 percent of silt. It should be noted that the mentioned tests were performed in three relative densities of 90, 95, and 100%, and the effect of geotextile layer was studied in two positions. In the first position, one geotextile layer was placed in the middle part of the soil sample, and in the second position two geotextile layers were alternatively placed in the samples. The results of laboratory studies show that putting one geotextile layer in samples helps modify and im-prove the bearing capacity. This increases were observed in the gravel and the gravel with 30% silt. However, putting two geotextile layers in the soil alternatively decreases resistance and bearing capacity of the samples. 

Anahtar Kelimeler

Gravel, Silt, California Bearing Ratio (CBR) Test, Soil Stabilization

Kaynakça

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