An Experimental Study on Stress Relaxation of a Silt-type Soil

Öz

In this study, stress relaxation tests were carried out by keeping specimens of a silt type soil under different strain levels. Decreases in the stress values with time data was collected to better understand the effect of the strain level on the relaxation properties of soil specimens. In addition, the stress relaxation effect on the uniaxial compressive strength (UCS) values of the specimens was investigated with a series of tests. According to the results obtained from this study, the UCS values of the silt specimens significantly vary as a result of the stress relaxation effect. The UCS values were determined to increase with an increase of relaxation strain level to a threshold value. On the other hand, the UCS values were found to be affected adversely in case of high stress levels at the initiation of the relaxation, which are close to the peak level.

Anahtar Kelimeler

• Stress relaxation
• time-dependent effect
• compressive strength of silts
• stress drop

Silt türü bir Zeminin Gerilme Rahatlaması üzerine Deneysel bir Çalışma

Öz

Bu çalışmada, farklı birim deformasyon seviyelerine tabi tutulan silt türü zemin numuneleri üzerine gerilme rahatlaması testleri gerçekleştirilmiştir. Gerilme değerlerinin zamana bağlı değişimleri ile farklı birim deformasyon değerlerinin gerilme rahatlaması üzerine etkileri incelenmiştir. Ayrıca, gerilme rahatlamasının tek eksenli sıkışma dayanımı (serbest basınç mukavemeti) değerleri üzerindeki etkileri bir dizi deneysel çalışma ile belirlenmiştir. Elde edilen bulgular, gerilme rahatlamasının tek eksenli sıkışma dayanımı (TESD) değerleri üzerinde önemli etkisi olduğunu göstermektedir. TESD değerleri belirli bir seviyeye kadar gerilme rahatlaması yaşanan birim deformasyon miktarı arttıkça yükselmiştir. Ancak, dayanım değerlerine yakın yüksek gerilme seviyelerinde başlayan rahatlamaların TESD değerlerini olumsuz etkilediği görülmüştür.

Anahtar Kelimeler

• Gerilme rahatlaması
• Zamana bağlı davranış
• Siltlerin sıkışma dayanımı
• Gerilme düşüşü

Kaynakça

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