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Asphalt pavement is among the most widespread road surfaces. For their design, assessment, and service life, it is necessary to evaluate the deformation characteristics of asphalt mixtures, which include the complex modulus of rigidity. Two-point (2PB-TR) and four-point (4PB-PR) flexural tests are used to determine these. The scientific paper focuses on the evaluation of the complex modulus as a function of varying temperature and frequency. The results of the study indicated that both methods provide significant information on the behaviour of asphalt mixtures under different loading conditions. Four-point bending may be more sensitive to changes in deformation properties than two-point bending. This finding is of fundamental importance when analysing the influence of different factors on the mechanical properties of asphalt mixtures. Measurements were performed at temperatures of 0°C, 10°C and 20°C and frequencies of 1 Hz, 5 Hz, 10 Hz, 15 Hz and 20 Hz. Validation of the different measurement methods was carried out on the comparison asphalt mix AC 11 O PMB 45/80-75.

Ventilation system of road tunnel is one of the most important parts of the tunnel safety equipment, especially in view of the emergency event in the tunnel with fire. Last year we presented the testing and the first in situ measurements of our project entitled “Models of formation and spread of fire to increase safety of road tunnels”. With regard to our project schedule we performed also the second in situ experiment. Other part of this paper deals with computer simulations of fires of a selected Slovak road tunnel.

Road emergency events are very dangerous, especially if they happen in tunnels. If such an event occurs with the presence of fire, self-evacuation is the most important. From experience from catastrophic events in Alpine tunnels, people can only have a few minutes to rescue. It was also reason that a lot of changes in technology and safety tunnel equipment have been legislatively adopted. Then if we want to help rescue people, we need experienced tunnel operators, who know the principles of tunnel ventilation control with fire and smoke. This paper is about simulation of emergency events in virtual tunnel of Tunnel Traffic & Operation Simulator (Simulator) and about simulations of smoke stratification on the basis of Computer Fluid Dynamics (CFD) models.

Within the project entitled “Models of formation and spread of fire to increase safety of road tunnels”, it was necessary to devise a method how to record airflow velocity during the fire in situ tests in road tunnels. Project is in first year of its solution so one testing measurement was performed to check the functionality of anemometers selected for this project and the first in situ measurement was also performed just a few days ago.

Tunnels, constructions used to shorten transport routes and to improve road safety, are specific engineering structures where the safe operation is very important. Tunnel Traffic & Operation Simulator (Simulator) was created as a solution of research task focused on increasing safety in road tunnels within the framework of the project “Centre of Transport Research (CVD)” funded by European Regional Development Fund (ERDF). The Simulator is located on Faculty of Civil Engineering of the University of Žilina (Slovakia) and is adapted to control the tunnel in two operator’s mode which are functionally convertible. They can during the operation of the simulator control the tunnel's technology and operation in normal conditions and in exceptional situations. Thanks to this, they could work under the pressure with non-performance threat to the tunnel technology and safety of their users. The coordinator checks and assesses the correctness of their conduct.