20.5 km of the 27.1 km long second track of the Divača-Koper railway line runs through tunnels, constructed in a karstic terrain. Based on the results from geological and hydrogeological tests, as well as the data from cave explorations, sections with a high possibility of crossing through karst formations during the excavation of tunnel tubes were determined. The aim of this Bachelor thesis is to describe one of the methods for the prediction of karst formations, called KarstALEA, and use of this method on the T2 tunnel. It was developed in Switzerland.
The first part of the thesis gives the overall description of the 2TDK project and certain design issues it presented. This is followed by a detailed description of the KarstALEA method, which can be divided into three phases. These are the initial judgement, ground investigation and using the KarstALEA method during construction. Additionally, four sets of tests are described: geological, hydrogeological, speleological and initial discontinuities tests. The third part of the thesis presents the tests, which were performed on the 2TDK track for tunnel T2, as well as those which will be performed in the future. To conclude, a comparison between the 2TDK project and the KarstALEA method is made. Although the tests for the 2TDK project did not follow the KarstALEA instructions to the letter, most tests were nonetheless taken into account. Based on this, it is clear that academic knowledge gathered from the KarstALEA method can be used practically during the tunnel design and construction phases.
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