Freezing-thawing behaviour of fine-grained soils subjected to surcharge loads

Öz

In cold climate zones, the shallow foundation soils belonging to civil engineering constructions such as highways, railways, irrigation channels are subject to freezing-thawing under these loads. In this study, with the purpose of representing such soils the freeze-thaw experiment has been carried out for the situation where load is applied on the samples in addition to the traditional method where there is no load on the sample. The experiments have been conducted on samples prepared with the compaction under standard proctor energy of fine grained soils. In the experiments conducted in the traditional method the unconfined compressive strength values of samples after 1, 3, 5 and 10 cycles have been determined. Then the freeze-thaw experiments were repeated while a load representing 25 %, 35 % and 50 % of these values was on the samples. As a result of the experiments conducted with both methods, the freeze-thaw resistances of the samples have been determined. It was observed that the freeze-thaw resistance values of soils under load are less than those found by the traditional method.

Anahtar Kelimeler

• Subject to loads of clay, Freezing-thawing, Unconfined compression strength.

Yüke maruz ince daneli zeminlerin donma-çözülme davranışı

Öz

Mevsimsel donma görülen soğuk iklim bölgelerinde karayolu, demiryolu, sulama kanalı gibi mühendislik yapılarına ait yüzeysel temel zeminleri bu yükler altında donma-çözülmeye maruz kalmaktadır. Bu çalışmada bu tür zeminleri temsil etmek amacıyla donma-çözülme deneyi geleneksel yöntemin yani numune üzerinde yük olmamasının yanı sıra numuneler üzerine yük uygulanması hali için de yapılmıştır. Deneyler, bir ince daneli zeminin standart proktor enerjisi altında sıkıştırılması ile hazırlanan numuneler üzerinde yürütülmüştür. Geleneksel yöntemde yapılan deneylerde 1, 3, 5 ve 10 çevrim sonunda numunelerin serbest basınç mukavemet değerleri belirlenmiştir. Daha sonra bu değerlerin % 25, % 35 ve % 50'sine karşılık gelen yük numuneler üzerinde iken donma-çözülme deneyleri tekrarlanmıştır. Her iki yöntem ile yapılan deneyler sonucunda numunelerin donma-çözülme dayanımları belirlenmiştir. Deney sonuçlarından üzerinde yük olan zeminlerin donma-çözülme dayanım değerlerinin geleneksel yöntem ile bulunanlardan daha az olduğu görülmüştür.

Anahtar Kelimeler

• Yüke maruz kil, Donma-çözülme, Serbest basınç mukavemeti.

Kaynakça

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