Stabilize Edilmiş İzmir Körfez Bölgesi Doğu Kıyı Şeridi Delta Zeminlerinin XRD ve SEM Analizleri

Abstract

İzmir Körfezi'nin Batı sahilinde Meles çayı, Arap ve Manda dereleri tarafından taşınmış yaklaşık 3 milyon metreküp kirlenmiş alüvyonel zemin bulunmaktadır. Bu akarsular, 300.000 m²‘lik bir deltayı paylaşmaktadır. Deltada bulunan alüvyonlar 10 ila 15 m kalınlığında yüksek su içeriği ve düşük taşıma kapasitesine sahip katmanlardan oluşmaktadır. Meles deltası zaman içerisinde, büyük ölçekli konut inşaat projelerinin yapımının başladığı şehrin doğu sahil şeridi içinde kalmıştır. Geniş bir alan işgal eden ve rekreasyon çalışmaları için bile uygun olmayan bu yumuşak birikintilerinin maliyet etkin bir şekilde stabilizasyonuna ihtiyaç duyulmaktadır. Ayrıca, yolcu gemilerinin İzmir Limanı'na yaklaşma kanalını derinleştirmek için delta alanının deniz dibi kısmının da taranması planlanmaktadır. Tarama yolu ile toplanacak kirlenmiş deniz sedimentlerinin depolanması da ayrıca çevresel bir sorun oluşturmaktadır. Bu çalışmada, kireç, çimento ve bunların farklı oranlarda karışımları kullanılarak, Meles Deltası zeminlerinin stabilizasyonu hedeflenmiştir. Optimum katkı oranlarını belirlemek için tek eksenli basınç deneyleri yapılmıştır. Stabilizasyon ürünlerini ve mikro yapıdaki değişiklikleri gözlemlemek için stabilize edilmiş zemin numunelerinde X-ışını kırınım (XRD) testleri ve taramalı elektron mikroskobu görüntülemesi (SEM) yapılmıştır. X-ışını testlerinde değişik oranlarda stabilizasyon ürünleri tespit edilmiştir. Ayrıca, işlenmemiş ve stabilize edilmiş zemin örneklerinin SEM görüntülerinin karşılaştırılması, mikro yapıda kalsiyum alümina hidratlar ve kalsiyum silika hidratların varlığını ortaya koymuştur. 

Keywords

• Zemin İyileştirme,Derin Karıştırma,Kireç-Çimento Karışımları,SEM,XRD

SEM and XRD Analyses of Stabilized East Coastline Delta Soils of Izmir Bay Area

Abstract

The gulf of İzmir contains 3 million cubic meters of polluted sediments carried by Meles, Arap and Manda rivers. These rivers share the same delta with a surface area approximately 300.000 m2, where 10 to 15 m thick sediment layers were deposited with high water content and low bearing capacity. The delta is now located along the east coastline of the city, where large scale residential building projects are under construction. These soil deposits that are unsuitable for the establishment of recreational facilities need to be stabilized in a cost-effective way. Besides, the sea bottom portion of the delta area will be dredged in order to deepen the approach channel of the cruise ships to the Izmir Port. The disposal of the contaminated sea sediments has also become an environmental concern. In this study, lime and cement and their mixtures with varying portions were considered as a stabilization agent for soft and contaminated sediments. Unconfined compression tests were conducted in order to determine the optimum additive percentages. X-ray diffraction tests (XRD) and scan electron microscope (SEM) imaging were performed on the stabilized soil specimens in order to observe the cementitious products and changes in the micro structure. In X-ray tests, cementitious by-products were detected in varying ratios. Also, the comparison of SEM images of untreated and stabilized soil specimens reveals the presence of calcium alumina hydrates and calcium silica hydrates in the micro structure.

Keywords

• Soil Improvment,Deep Mixing,Lime-Cement Mixtures,SEM,XRD

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