4 research outputs found
YANAL YÜKLÜ BİR MODEL KAZIĞIN KUM ORTAMINDAKİ DAVRANIŞININ DENEYSEL VE NÜMERİK YÖNTEMLERLE İNCELENMESİ
Bu çalışmada, farklı kum ortamlarında yerleştirilmiş olan bir kazık modelinin yanal yüklemeler altındaki gerilme-şekil değiştime ve yerdeğiştirme davranışı incelenmiştir. Labaratuvar ortamında yürütülen çalışmada, dairesel bir alüminyum kazık, deney kutusu, yükleme düzeneği, yer değişimi ve şekil değişimi ölçerler kullanılmıştır. Yağmurlama sistemi kullanılarak eşdeğer sıkılık ve homojen bir dolgu ortamı oluşturulmuştur. Deneysel çalışmalarda model kazığın kademeli yüklemeler altındaki gösterdiği davranışı deneysel olarak saptanmıştır ve daha sonra kazık davranışı, tasarımcılar tarafından yaygın olarak kullanılan p-y ve yatak katsayısı yöntemleri kullanılarak analiz edilmiştir. Nümerik çalışmalar LPILE ve SAP 2000 programlarında gerçekleştirilmiştir. Yapılan çalışmalar sonucunda, p-y yönteminin yatak katsayısı yönteminden daha güvenilir sonuçlar ortaya koyduğu saptanmıştır. Kumun sıkılık derecesinin zemin reaksiyonu üzerindeki etkisi görülmüştür. Son olarak ölçüm aygıtlarının kalibrasyonunda kullanılan Daley yönteminin güvenilir olduğu anlaşılmıştır
The Space-Borne SBAS-DInSAR Technique as a Supporting Tool for Sustainable Urban Policies: The Case of Istanbul Megacity, Turkey
In today’s urbanizing world, home of 28 megacities, there is a growing need for tools to assess urban policies and support the design and implementation of effective development strategies. Unsustainable practices of urbanization bring major implications for land and environment, and cause a dramatic increase of urban vulnerability to natural hazards. In Istanbul megacity, disaster risk reduction represents a challenging issue for urban managers. In this paper, we show the relevance of the space-borne Differential SAR Interferometry (DInSAR) technique as a tool for supporting risk management, and thus contributing to achieve the urban sustainability. To this aim, we use a dataset of high resolution SAR images collected by the TerraSAR-X satellite that have been processed through the advanced (multi-temporal) Small BAseline Subset (SBAS)—DInSAR technique, thus producing spatially-dense deformation velocity maps and associated time-series. Results allow to depict an up-to-date picture of surface deformations occurring in Istanbul, and thus to identify urban areas subject to potential risk. The joint analysis of remotely sensed measurements and ancillary data (geological and urban development information) provides an opportunity for city planners and land professionals to discuss on the mutual relationship between urban development policies and natural/man-made hazards
The Space-Borne SBAS-DInSAR Technique as a Supporting Tool for Sustainable Urban Policies: The Case of Istanbul Megacity, Turkey
In today’s urbanizing world, home of 28 megacities, there is a growing need for tools to assess urban policies and support the design and implementation of effective development strategies. Unsustainable practices of urbanization bring major implications for land and environment, and cause a dramatic increase of urban vulnerability to natural hazards. In Istanbul megacity, disaster risk reduction represents a challenging issue for urban managers. In this paper, we show the relevance of the space-borne Differential SAR Interferometry (DInSAR) technique as a tool for supporting risk management, and thus contributing to achieve the urban sustainability. To this aim, we use a dataset of high resolution SAR images collected by the TerraSAR-X satellite that have been processed through the advanced (multi-temporal) Small BAseline Subset (SBAS)—DInSAR technique, thus producing spatially-dense deformation velocity maps and associated time-series. Results allow to depict an up-to-date picture of surface deformations occurring in Istanbul, and thus to identify urban areas subject to potential risk. The joint analysis of remotely sensed measurements and ancillary data (geological and urban development information) provides an opportunity for city planners and land professionals to discuss on the mutual relationship between urban development policies and natural/man-made hazards