Metodología de diseño, observación y cálculo de redes geodésicas interiores en túneles de ferrocarril de alta velocidad

The guiding of TBMs (Tunnel Boring Machines) along their advance must be based on points placed immediately behind them. Achieving good accuracies results would present some difficulties for normal exterior conditions, but inside a tunnel certain factors clouding the outlook arise. The most important and difficult factor to deal with, has to do with lateral refraction. Internal geodetic networks design is one of the more challenging problems from the geodetic and topographic point of view, as the bibliographical review dealing with this subject, advises to avoid this practice. This network allows only guiding the TBM, so that it is not used for further checking or quality control. As the network progresses, the reached coordinate accuracies deteriorate exponentially. This work establishes a methodology for the design of internal horizontal networks.