PRACTICAL CONSEQUENCES OF THE TIME-DEPENDENCY OF GROUND BEHAVIOR FOR TUNNELING

摘要

Time-dependent ground behavior may have important implications for the construction process or the life of a tunnel. The paper gives a concise overview of the influence of time on the deformations and the stability of underground openings, including topics such as face stability in soft ground or the time-development of pressure or deformations in squeezing or swelling rock. While keeping in mind practical questions of tunnel engineering, emphasis is placed on understanding the observed time-dependency, on the underlying mechanisms (such as porewater pressure dissipation or chemical processes) as well as on the respective inherent predictionuncertainties and design-uncertainties.