Gyromätning i tunnelnät : Gyromätningens påverkan på kortare stomnät i tunnelmiljö

Sammanfattning: Geodetic measurements with a gyro theodolite are an important technique for establishing control networks in tunnelling projects. The observations are used as a separate control point outside the main network while checking the angle of the tunnels direction as it is difficult to connect the underground network to a superior network outside the tunnel.  This study aims to investigate the usefulness of gyro surveys in tunnel networks and evaluate how much they improve the positional accuracy of underground control networks. The study compares a total of four network simulations (with and without gyro observations) that have been divided into 12 sections. The sections are then compared to each other to determine the influence of gyro observations on the positional uncertainty in the network. Gyro observations were found to contribute to significant improvements in measurement data. Without them the tunnel would have an uncertainty greater than five centimetres within approximately 1000 m. The results provide valuable insights into the impact of gyro measurements on geodetic control network in tunnels and how they can be used to improve measurement data.