Influence of groundwater level rise on the geomechanical changing process in the tunnel surrounding jointed rock mass and in the tunnel support structure

In the practical construction of underground excavations, the groundwater level in the surrounding rock masses can fluctuate due to water accumulation (reservoirs), water abstraction and, in particular, due to the consequences of climate change. This fluctuation causes changes in the geomechanical state of the rock mass and effects on the support structure. This phenomenon and its effects must be predicted in order to get appropriate suggestion for the design and construction measures. The article presents some simulation results that analyse the redistribution of geomechanical processes in the jointed rock mass around a tunnel with and without support as well as the rule of the changes of the internal forces in the support structure when the groundwater level changes by using UDEC.