Anhydrite is a calcium sulfate mineral that is often found in the geological structure of the rock mass in our region and is often the cause of challenges in tunnel construction. The presence of anhydrite can significantly affect the financial and time aspects of construction, as well as the stability of the tunnel and subsequent rehabilitation works; therefore, a good knowledge of the subject is important. The challenges that arise are the swelling of anhydrite, the formation of caverns and the presence of aggressive sulfate water that damages concrete. The swelling of anhydrite due to the presence of water is a phenomenon that causes large deformations and pressures on the tunnel lining, which can also lead to tunnel collapse. Another issue is the dissolution of anhydrite, which causes the formation of caverns and can also threaten the stability of the tunnel. Despite the great deal of research and experiences on this topic, the presence of anhydrite still represents a big challenge that is difficult to overcome. The problems arise mainly with the assessment of the swelling and dissolution potential and subsequently with selecting the appropriate measures. The master’s thesis presents the problem of the presence of anhydrite in the rock, and the various tests and methods that can help us in researching the conditions and assessing the potential for the course of both processes. The thesis also describes various past and present measures to resolve the problem of the reaction of anhydrite with water in the short and long term. On the example of the Ivan tunnel in Bosnia and Herzegovina, the problems of anhydrite swelling and the occurrence of caverns are presented. We also describe the measures used to solve the problem during construction.
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