GNSS Tekniği ile Düşey Yöndeki Deformasyonların Araştırılması

Yerkabuğunda ve mühendislik yapılarında deformasyonların izlenmesi ve analizi jeodezinin önemli konuları arasında yer almaktadır. Deformasyonların izlenmesi amacıyla genel olarak referans ve obje noktalarından oluşan bir jeodezik ağ oluşturulur. Ağ noktalarındaki hareketler analiz edilerek deformasyon araştırması yapılır. Bu hareketlerin belirlenmesine yönelik ölçmeler klasik teknikler ile yapılabileceği gibi GNSS teknikleriyle de yapılabilmektedir. Statik konum belirleme yöntemi, bu tür hassas jeodezik uygulamalarda yaygın olarak kullanılan bir yöntemdir. Bu çalışmada; GNSS tekniğinin düşey yönlü deformasyonları belirleyebilme kapasitesi araştırılmıştır. Bu amaçla, Selçuk Üniversitesi Kampüs alanında bir mikro jeodezik ağ tasarlanmıştır. Tasarlanan ağda obje noktası üzerine sanal deformasyonlar oluşturmaya yarayan bir düzenek yerleştirilmiş ve düşey yönde sanal deformasyonlar meydana getirilerek periyot ölçüleri gerçekleştirilmiştir. Periyot ölçüleri Bernese v5.2 bilimsel GNSS yazılımı ile değerlendirilmiş, GNSS ağlarında deformasyon analizi gerçekleştirmek amacıyla geliştirilen yazılım kullanılarak İteratif Ağırlıklı Benzerlik Dönüşümü Yöntemiyle analiz edilmiş ve belirlenen deformasyonlar ölçü günlerindeki iyonosferik aktiviteler de dikkate alınarak sanal deformasyon değeriyle kıyaslanmıştır. Analizler sonucunda sanal deformasyon değeriyle uyuşumlu vektörel deformasyon büyüklükleri elde edilmiş ve koordinat bileşenleri yönündeki hareket büyüklüklerinin de düzenek üzerinde verilen sanal deformasyon miktarıyla uyuşumlu olduğu görülmüştür.

Investigation of Vertical Deformations with GNSS Technique

Monitoring and analysis of deformations in the earth's crust and engineering structures are among the important issues of geodesy. In order to monitor the deformations, a geodetic network consisting of reference and object points is created in general. Deformation research is carried out by analyzing the movements at the network points. Measurements for the determination of these movements can be made with classical techniques as well as with GNSS techniques. The static relative positioning is a widely used method in such precise geodetic applications. In this study; the capacity of the GNSS technique to detect vertical deformations was investigated. For this purpose, a micro geodetic network was designed in the Selcuk University Campus area. A mechanism to create virtual deformations was placed on the object point in the designed network and periodic measurements were carried out by creating virtual deformations in the vertical direction. Measurements were processed with the Bernese v5.2 scientific GNSS software, analyzed by Iterative Weighted Similarity Transformation Method using the software developed to perform deformation analysis in GNSS networks, and the determined deformations were compared with the real deformation value, considering the ionospheric activities on the measurement days. As a result of the analyses, vectorial deformation amounts compatible with the real deformation value were obtained and it was seen that the motion amounts in the direction of the coordinate components were also compatible with the virtual deformation amount given on the mechanism.

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