ABSTRACT

Abstract:The positioning of an object in space, i.e. "transfer" of data from the design to the field is an extremely significant and important geodetic operation. This activity requires great and well-deserved attention, especially when it comes to sensitive structures such as bridges. The position of a stakeout point in the field depends on a variety of different influences, all determining the actual accuracy of the stakeout. The aim of this Article is to investigate the dependency of horizontal setting out of the bridge axis accuracy (abutments and piers of the bridge) from the distance between the station and the setout point, the datum of the geodetic control network, and the precision of angular and linear measurements. The authors use an innovative visualization technique for the assessment of spatial variation of the horizontal stakeout by error ellipses.

deformation analysis, robust methods, numerical example This article describes the deformation analysis approach with robust methods in geodetic networks. The characteristic of this approach is the iterative weighted similarity transformation in which the displacement vector d is transformed into a datum determined by points with a smaller coordinate difference between two epochs. The article first gives a theoretical background of the approach, and then the approach is applied to the case of simulated measurements in two epochs. The calculated results of the deformation analysis approach with the robust methods in the present case do not differ significantly from the results obtained by conventional deformation analysis approaches.

No abstract

No abstract