Development and significance of monitoring and evaluation methods in tunnel construction – From NATM to asset safety management

Abstract

This article provides a historical overview of the development of monitoring and evaluation methods and their significance for tunnel construction. Systematic measurements began in the mid‐1950s and, particularly following the widespread adoption of the New Austrian Tunnelling Method (NATM), have become a fundamental component of the monitoring of tunnelling and support. The article traces the continuous advancement of monitoring and observation methods, including their evaluation and integration. The assessment of rock mass and lining behaviour resulting from the interaction between the rock mass and the lining during tunnel excavation has long played a key role in geotechnical safety management. In addition, ongoing monitoring during the operational phase is becoming increasingly important for assessing the condition of structures as part of asset safety management. Measurement data relating to displacements and strains are incorporated into numerical and analytical models to determine the stress in the tunnel lining. This enables trends in load‐bearing behaviour to be identified, potential weak points to be detected at an early stage and repair measures to be planned in a targeted manner. Consequently, monitoring makes a significant contribution to safety, system availability and cost‐effectiveness. The article concludes with a description of the current state of the art.