This thesis describes the implementation of sensor-based feature analysis, in the form of online- analysis, for the characterization of excavated tunnel material. Due to the increasing climate protests and measures for CO2- reduction, there is a motivation to find new approaches, so that the construction industry meets all ecological goals in the future. In addition, the interconnectedness of society leads to the construction of infrastructure projects, which are constantly increasing in size. Especially in tunnel construction projects there is, with the construction of base tunnels, a large amount of excavated tunnel material, which is currently often landfilled. Landfilling is neither the aim of the intended circular economy nor of the environmental impact assessment required in the approval phase. This work addresses an approach to recycling this material stream. The online- analysis characterizes the accumulating material flow directly at the conveyor belt, by the emission of electromagnetic waves of different wavelengths. Due to the different reflection or absorption behaviour of the geomaterials, the material parameters are derived from the detected radiations. Through an extensive research on sensor technologies and possibilities for the detection of rock properties in connection with requirements for possible end products, the implementation of an online- analysis system on a tunnel construction site is examined. Based on the different application possibilities as well as the advantages and disadvantages, the suitability of each sensor technology is evaluated. Subsequently, a prototype system will be assembled from the resulting sensor combination, both for cyclic and continuous tunnelling. An online- analysis system brings additional requirements to the project management of a tunnel project. For this purpose, a process is created which considers the implementation of an online- analysis system in the current tunnel construction process in order to obtain promising results in the future. Furthermore, approaches for the digitalization of a tunnel construction site are mentioned. This is built by combining the data from tunnelling and online- analysis. Finally, the advantages of integrating an online- analysis system on a tunnel construction site are explained.