Numune Örselenmesinin Geleneksel Ödometre Deneyleri ile Belirlenen Konsolidasyon Parametrelerine Olan Etkilerinin İncelenmesi

Öz

Bu çalışmada, numune örselenmesinin geleneksel konsolidasyon deneyleriyle elde edilen sıkışma eğrileri ve ön konsolidasyon gerilmesine (sp') olan etkileri incelenmiştir. Laboratuvara getirilen numuneler sistematik olarak %10, %20, %30, %40 ve %50 oranında içleri boşaltılıp geri doldurularak örselenmiştir. Örselenme oranının artmasıyla, sıkışma eğrisi üzerinde sp' değerlerinin belirlenmesinin giderek zorlaştığı, sıkışma eğrisindeki tipik büküm noktasının giderek belirginsin bir hale geldiği ve %40 örselenme oranına kadar örselenen zemin numunelerinin sp' değerlerinde önemsenmeyecek miktarda değişimlerin olduğu tespit edilmiştir. Ön konsolidasyon gerilmesi gibi konsolidasyon parametrelerinin belirlenemediği zemin numunelerinin %40'dan daha fazla örselenmeye maruz kaldığı ve bu tür örnekler üzerinde konsolidasyon parametrelerinin belirlenmemesi gerektiği önerilmektedir.

Anahtar Kelimeler

• Sistematik Numune Örselenmesi
• Ön Konsolidasyon Gerilmesi
• Odometre Deneyi
• Konsolidasyon Parametreleri

Investigation of the Sample Disturbance Effects on Consolidation Parameters Obtained from Conventional Oedometer Tests

Öz

This study explores the effects of sample disturbance on the compression curves obtained from oedometer tests and the inferred effective preconsolidation stress (sp'). The samples were systematically disturbed by removing different fractions of the soil ranging from 10%, 20%, 30%, 40%, and 50% and remolding them back into place to reach the same initial void ratio. It was found that when the rate of disturbance was increased, it became more difficult to determine the sp' values on the compression curve; the typical bending point on the compression curve became increasingly indistinct, and negligible changes occurred in the sp' values of the disturbed soil samples up to a disturbance rate of 40%. If the soil samples whose consolidation parameters such as preconsolidation stress can’t be determined are subjected to disturbances greater than 40%, it is recommended that no consolidation parameter of such samples be specified.

Anahtar Kelimeler

• Systematic Sample Disturbance
• Preconsolidation Stress
• Oedometer Test
• Consolidation Parameters.

Kaynakça

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