Sille Hamurda Kayasının Bozunma Davranışının Araştırılması

Yıl 2021, Cilt: 42 Sayı: 2, 179 - 198, 20.08.2021

Elif Avşar

https://doi.org/10.17824/yerbilimleri.910036

Öz

Bilindiği gibi hamurda kayalar blok ve matriks olmak üzere iki bileşenden oluşmaktadırlar. Bu kayaların dayanım, deformasyon ve bozunma davranışının araştırılmasında hamurda kaya ile birlikte blok ve matriksin jeo-mekanik özelliklerinin ve bozunma karakteristiklerinin belirlenmesi oldukça önemlidir. Bu çalışmada hamurda kayanın donma-çözünme ve suda dağılmaya karşı duraylılık olmak üzere iki süreç açısından fiziksel bozunma davranışı araştırılmıştır. Buna ek olarak, bu tür bir kayanın yerinde ve dolayısıyla zaman açısından doğal sürecinde bozunması sonucu dayanımındaki azalma gözlenmiştir. Bu amaçla bozunmaya bağlı olarak dayanım azalmasının yerinde tayin edilmesi için Sille Antik Kenti’ndeki (Konya) kaya oyma yapılarının duvarlarında Schmidt çekici deneyleri uygulanmıştır. Laboratuvar ve arazi çalışmalarının tümünde hamurda kayayı oluşturan matriks ve blok bileşenleri ve hamurda kayanın kendisi ayrı ayrı incelenmiştir. Ayrıca, laboratuvar ve arazi ölçeğinde bozunma sonucu hamurda kayada ve hamurda kaya kütlesinde gerçekleşen fiziksel değişimler birbiriyle ve diğer volkanik/volkanoklastik kayalarla karşılaştırılmıştır. Sonuçlara göre, hamurda kaya ve matriksin suda dağılmaya karşı duraylılığının düşük olduğu belirlenmiştir. Buna karşın, blokların suda dağılmaya karşı duraylılık indeksinin matriks ve hamurda kayanın suda dağılma indeks değerlerine oranla oldukça yüksek olduğu belirlenmiştir. Donma-çözünme çevrimleri sonunda hem hamurda kayada hem de blok ve matrikste tek eksenli sıkışma dayanımının kritik biçimde azaldığı belirlenmiştir. Blokların Schmidt geri sıçrama değerlerinin matrikse ait değerlerden daha yüksek olduğu ve kaya yapılarının dış duvarlarındaki geri sıçrama değerlerinin iç odaların duvarlarında ölçülenlerden belirgin biçimde düşük olduğu ortaya konmuştur.

Anahtar Kelimeler

Bozunma, donma-çözünme, hamurda kaya, antik kaya yapıları

Destekleyen Kurum

Selçuk Üniversitesi

Proje Numarası

17401137

Teşekkür

Bu çalışma, Selçuk Üniversitesi (Konya) Bilimsel Araştırma Projeleri (BAP) birimi (Proje no. 17401137) tarafından mali olarak desteklenmiştir. Schmidt çekici deneylerinin uygulanması ve örneklerin derlenmesi aşamalarındaki desteklerinden dolayı Araş. Gör. Dr. Ali Bozdağ’a (Konya Teknik Üniversitesi) teşekkür ederim.

Investigation of Weathering Behaviour of Sille Bimrock

Öz

As is known, bimrocks are composed of two constituents, blocks and matrix. It is crucial to determine the geo-mechanical properties and weathering characteristics of bimrock, blocks and matrix, individually, while studying on the strength, deformation and weathering behaviour of these rocks. In this study, physical weathering behaviour of bimrock was investigated in terms of two processes such as freezing-thawing and slake durability. In addition, strength reduction because of weathering of such rock has been observed in situ and therefore in its natural process in terms of time. For this purpose, Schmidt hammer tests were applied on the walls of the rock-hewn structures in Sille Antique City (Konya) in order to determine the strength reduction due to the in-situ weathering. The matrix and block constituents that compose the bimrock and the bimrock itself were separately examined in all of the laboratory and field studies. In addition, physical changes in the bimrock and bimrock mass because of weathering were compared both for laboratory and field scale and with the weathering behaviour of other volcanic/volcanoclastic rocks. The results suggested that the bimrock and matrix have very low slake stability. On the other hand, it was determined that the slake durability index of the blocks is quite higher than the durability index of the matrix and the bimrock. It was revealed that the uniaxial compressive strength of the bimrock, block and matrix decrease critically when subjected to the freezing-thawing cycles. The Schmidt rebound values of the blocks are higher than values of matrix, and the rebound values on the outer walls of the rock structures are significantly lower than determined on the walls of the inner chambers.

Anahtar Kelimeler

Antique rock-hewn structures, bimrock, freezing-thawing, weathering

Proje Numarası

17401137

Kaynakça

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