COLLAPSE OF BASE SOIL AND ITS CONSEQUENCES DURING A CEMENT PLANT CONSTRUCTION

Abstract

Collapsible soils are subjected to rapid changes in their volume when inundated with water. Collapse of such a soil deposit during construction of a cement plant in north Azerbaijan resulted in significant settlement and tilting of structures causing a 2 years delay in the construction. The investor had to bear the huge costs of delay and remediation works. The collapse susceptibility of the soil could not be identified during initial site investigations. After first indications of the collapse problem (tilting, cracking of structures) the settlements were measured at different locations for a long time and a new site investigation was executed. The results of these studies were utilized to determine the collapse potential of the soil. Interestingly, some of the indirect methods were not capable of determining the collapse potential. It was seen that, indirect methods may mislead the engineers in such soils and it is more reliable to perform direct tests to determine collapse potential in similar soil deposits. In this study, it is aimed to discuss the experience gained in this project about determining the collapse potential and apprise the professionals as well as academicians about possible problems which may be faced during such studies in similar soils.

Keywords

• Collapse
• Settlement
• Tilt

Bir Çimento Fabrikası İnşaatı Sırasında Gözlemlenen Zemin Çökmeleri ve Sonuçları

Öz

Çökebilen zeminler suya maruz kaldıklarında hacimsel olarak hızlı değişimler gösterirler. Kuzey Azerbaycan’daki bir çimento fabrikası inşaatı sırasında meydana gelen bu tarz bir zemin çökmesi, yapıların kayda değer miktarda oturmasına ve eğilmesine sebep olmuş ve inşaatın yaklaşık 2 yıl kadar gecikmesine sebebiyet vermiştir. Yatırımcı, tamirat işleri ve gecikmeler sebebiyle oluşan ciddi maliyetleri karşılamak zorunda kalmıştır. Zeminin çökme potansiyeli yapılan ilk saha etütlerinde belirlenememiştir. Eğilme ve/veya yapılardaki çatlaklar gibi çökmeden kaynaklı ilk belirtilerden sonra, çeşitli noktalarda uzun süreli oturma ölçümleri alınmış ve yeni, daha detaylı arazi etütleri planlanmıştır. Bu çalışmaların sonuçları, zeminin çökme potansiyelini belirlemek için kullanılmıştır. Literatürde belirtilen dolaylı metotların bazıları ilginç bir şekilde çökme potansiyelini belirleyememiştir. Yapılan araştırma sonucunda, bu tip zeminlerde bazı metotların mühendisleri yanlış sonuçlara yönlendirebileceği; benzer zeminlerde çökme potansiyelini direk metotlarla belirlemenin daha güvenilir bir yöntem olduğu görülmüştür. Bu çalışmanın amacı, projede sırasında bu tip zeminlerin çökme potansiyelinin belirlenmesi konusunda kazanılmış tecrübeleri tartışmak ve hem akademisyenleri hem de bu alandaki profesyonel kişileri benzer zeminlerde, bu tarz çalışmalar sırasında oluşabilecek sorunlar hakkında bilgilendirmektir.

Anahtar Kelimeler

• Çökme
• Eğilme
• Oturma

Kaynakça

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