Two of the most important factors influencing the decision whether and how the tunnel will be built are the estimated construction time and cost. The aim of this master’s thesis is developing a methodological procedure and creating a program that automatically calculates the advance rates for tunnel excavation and support based on the given geological conditions for construction. The program is intended for use in the design phase with the aim of optimizing the calculation of the critical path, which determines the shortest tunnel construction time. The basis for designing tunnels using the New Austrian Tunnelling Method (NATM) is the theory of the ground reaction curve. The NATM method is developed in such a way that we are able to determine the optimal ratio between the level of deformations in the ground and the thickness of the primary lining, which directly dictates the costs and the overall stability conditions of construction. The Austrian standard ÖNORM B-2203 classifies the excavation with the help of numerical indicators according to the size of the excavation face, the amount and type of supporting elements. This is essential for objectively determining the excavation cost in a specific support number.
The program for calculating advance rates was applied to the case of the Vodriž tunnel. The input data for the program are, on one hand, data on the quantities of excavation and support, the method of excavation and the type of supporting elements. On the other hand, basic time parameters are derived from the contractor’s time norms for individual work sequences and also from various studies on the speed of progress of excavation works.
The code of the program is written using programming language C++, as the purpose is to integrate the program into the already existing software tool MatM, developed by IRGO Consulting d.o.o. MatM is used to process support numbers according to the selected excavation and support parameters.
The purpose of this master’s thesis was to define the individual phases of excavation and support and establish a more precise connection between the numerical values of support types and the corresponding advance rates. The general applicability of the program lies in the direct application of resulting advance rates in the critical path. With this, it is possible to determine a large part of the variable time of the critical path (excavation and support).
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