Iskanje po katalogu digitalne knjižnice

Opis: Displacement research using the three-dimensional global navigation satellite system (GNSS) as part of geodetic monitoring is becoming the key investigation for establishing a cause-and-effect relationships model between external natural factors, on the one hand, and the criteria that describes the level of functionality and safety of the observed natural or artificial object, on the other, in cases of motion of an object in space and time. The main objective of the deformation analysis is to confirm the stabilities of the reference points of a geodetic network, which are used to determine the movements of the control points that are stabilized on the observed objects. The assumption about the stabilities of certain reference points must be based on reasonable grounds, underpinned by measurements and proven by numerical methods. This is one part of the results of the deformation analysis when determining the extent of the movements and deformations. To do this a transformation is used in which a comparison is made between the coordinates of the points for two separate epochs. On the basis of the estimated transformation parameters, possible movements can be concluded within the reference points, i.e., on whether the datum parameters have changed. After confirming the stability of the geodetic network the coordinate differences of identical points measured within the different time windows can be determined as displacements and/or deformations of an object. In this paper one viaduct was assessed through geology and tectonic activities and also a load test of the viaduct was performed. The viaduct is in a quite active region, but the load test showed that the bridge response to the load is as expected.
Ključne besede: geodesy, geotehnics, monitoring, GNSS measurements, geology, deformation analysis, geodetic network
Objavljeno v DKUM: 18.06.2018; Ogledov: 1392; Prenosov: 64
Celotno besedilo (630,78 KB)
Gradivo ima več datotek! Več...

Opis: Deformation measurement experiment has been undertaken where a concrete structure was subject to controlled loading. Concrete plate was loaded with hydraulic cylinder PZ 100 up to 42 kN. Nikon total station ser. 720 and camera Fuji Pro S3 have been used to make measurements at critical points during each additional load. A hydraulic computer operated cylinder was used for load increase. The use of total stations for deformation measurements is quite often, but the combination with digital photography is rather new and very suitable technique. It offers the capability of simultaneous monitoring of a large number of signalized or non-signalized points with very low root mean square error of 0.16 mm in geodetic method 0.7 mm in photogrammetry, respectively. The concrete plate was modeled and the comparison with the geodetic, photogrammetric and hydraulic method was made.
Ključne besede: deformation measurements, geodesy, digital photogrammetry
Objavljeno v DKUM: 31.05.2012; Ogledov: 3347; Prenosov: 52
Povezava na celotno besedilo