Results from a comprehensive GPS Network: natural gas pipeline GPS Network

Abstract

Developing the Nabucco engineering infrastructure was the most challenging task imaginable and required state-of-the-art technologies. For this purpose, a Nabucco-Global Positioning System (GPS) Network was established. It is 762 km long. Nine-hundred and two ground control unit points were established. In order to provide the relationship with ITRF96 datum, it was surrounded by TFNGN (Turkish Fundamental National GPS Network) and TNVCN (Turkish National Vertical Control Network) checkpoints. GPS observations were evaluated in the form of a unique network. After being reduced to projection segments, coordinates in ED50 datum were provided between datums by 2D-Helmert Transformation. Orthometric heights related to the GPS Network were obtained by the improvement of TG-03 data based on a GPS/leveling procedure. The objective of the study is to present the results of a comprehensive engineering project which involved many geodetic considerations including GPS, orthometric heights, and geoid undulations and gives insight into the accuracy and precision of such large projects in terms of recent geodetic practice. In this study, a Global Navigation Satellite System (GNSS)-based geodetic infrastructure is presented, methods to obtain the necessary precision requirements are provided, and experience is shared in order to provide an example of a large-scale pipeline project, and to provide insight into the planning necessary for future similar engineering projects.