Resource‐efficient tunnel segment with butt‐jointed reinforcement in the longitudinal joint

The optimization of constructions is becoming increasingly important in view of the growing scarcity of resources. There is considerable potential for increasing the efficiency of tunnel shells in segmental lining by making targeted adjustments to the design and dimensioning of the tunnel segments. A reinforcement concept developed at the Technical University of Vienna offers the opportunity to increase the load‐bearing capacity of the segments and optimize resource consumption. This design with butt‐jointed longitudinal bars was investigated using large‐scale test specimens representing sections of tunnel segments. The tests were carried out in a test frame with a maximum load of 18 MN, which made it possible to test common segment thicknesses of 40 cm on a scale of 1:1. While the experimental loads for the test specimens have already been set in relation to the global warming potential of the materials used in the past, deviating results can be assumed for real segment geometries. By transferring the tests to fictitious, realistic tunnel segments, this work clearly shows that the improved resource efficiency of the reinforcement concept is particularly evident when entire segments are considered. In addition, in contrast to the purely centric test results, considerations are made regarding the handling of eccentricities. Here, the possibilities for arranging the longitudinal bars can be demonstrated using a fictitious segment.