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

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.

Yüke maruz ince daneli zeminlerin donma-çözülme davranýþý

Mevsimsel donma görülen soðuk iklim bölgelerinde karayolu, demiryolu, sulama kanalý gibi mühendislik yapýlarýna ait yüzeysel temel zeminleri bu yükler altýnda donma-çözülmeye maruz kalmaktadýr. Bu çalýþmada bu tür zeminleri temsil etmek amacýyla donma-çözülme deneyi geleneksel yöntemin yani numune üzerinde yük olmamasýnýn yaný sýra numuneler üzerine yük uygulanmasý hali için de yapýlmýþtýr. Deneyler, bir ince daneli zeminin standart proktor enerjisi altýnda sýkýþtýrýlmasý ile hazýrlanan numuneler üzerinde yürütülmüþtür. Geleneksel yöntemde yapýlan deneylerde 1, 3, 5 ve 10 çevrim sonunda numunelerin serbest basýnç mukavemet deðerleri belirlenmiþtir. Daha sonra bu deðerlerin % 25, % 35 ve % 50’sine karþýlýk gelen yük numuneler üzerinde iken donma-çözülme deneyleri tekrarlanmýþtýr. Her iki yöntem ile yapýlan deneyler sonucunda numunelerin donma-çözülme dayanýmlarý belirlenmiþtir. Deney sonuçlarýndan üzerinde yük olan zeminlerin donma-çözülme dayaným deðerlerinin geleneksel yöntem ile bulunanlardan daha az olduðu görülmüþtür.