Design of safety tunnels in railway tunnels

In this study, the security escape tunnels being constructed in tunnels located on Ankara-Istanbul High Speed Train Route were examined being explained the security measures suggested by the International Railway Association against possible risks, hazards and accidents in High Speed Railway Tunnels. The Security Tunnel T-35-GT2 was selected as the study subject, which is being constructed in 3255 meter long Tunnel T35 located on Ankara-Istanbul High Speed Train Line Km: 232+031-236+031. The Safety Tunnel T35-GT2 which is 224 meter long and %6 sloped, The Safety Tunnel section was determined as 5 meter high and 4,5 meter wide by TCDD in order to ensure the ambulance and fire brigade transition in any emergency situation. In order to set the tunnel geological model, two boreholes were drilled and with the cores and the laboratory tests taken from these boreholes, rock parameters were determined. According to these parameters, the tunnel is divided into 3 regions and the performances of the support systems for each zone are examined with the Phase2 V8.014 computer program. At the conclusion of this study, it is appeared that the rock conditions with a slight or no effect of discontinuity can be estimated by using numerical analysis while in case that the discontinuities couldn't be estimated by drilling and surface observations, some problems caused by deficient data were encountered in the estimation done being used numerical analysis. Thus it is obviously seen that the importance of checking the field data frequently which was estimated during the tunnel construction and revising of the support system, in case of a necessity.