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Key to understanding the needs and tools of road infrastructure management for preventing runoff-road crashes or minimising their consequences, is to identify the hazards and sources of hazards caused by wrong or improper use of road safety devices and identify errors in the design, structure, construction and operation of road safety devices. Studying such an extended scope of the problem required fieldwork and surveys with road authorities, designers, road safety auditors and road maintenance services. An outline of new guidelines could only be developed after understanding the effects of restraint systems, the design, additional elements, type of road and safety barrier location on a road or engineering structure and the road and traffic conditions on their functionality and safety. The paper will present the preliminary results of this research (research project – ROSE). One way to understand the functionality of road safety devices is to build numerical models and conduct simulation tests of virtual crash tests. The article presents the scope of work conducted as part of an effort to develop new vehicle restraint system guidelines.

The article describes a comparison of two general methods of occupants safety estimation based on a numerical examples. The so-called direct method is mainly based on the HIC (Head Injury Criterion) of a crash test dummy in a vehicle with passive safety system while the indirect method uses a European standard approach to estimate impact severity level.

The paper presents the maturity curve for estimating the in-place early-age compressive strength of concrete. The development of appropriate maturity curve is a complex process. It is important to correctly determine the datum temperature and activation energy, which can be obtained in mortar tests. This paper describes an investigation of the accuracy of the maturity method to estimate the strength when different way to rate constant and maturity function are analysed. High performance concrete used for construction of extradosed bridge was tested. The developed curve was implemented to predict the concrete strength at three construction stages, in summer, autumn and early spring.

Damages of spans of the overpass caused by impact of underpassing vehicles are relatively frequent. Objects that use prefabricated load-bearing elements that are not designed for such impacts are particularly exposed. After impact, such structural elements suffer extensive damage that must be repaired. Taking advantages of this recovery actions it is worth to perform strengthening that will protect object against possible future impacts. In this study the influence of the structural strengthening of the damaged overpass on its strength parameters is investigated. For this purpose the advanced computational model was created. The numerical model includes the response of the reinforcement and prestressing tendons. This model enables precise description of damage caused due to the vehicle‘s impact and further analysis of re-impact of the strengthened structure.

Road safety barriers are used to increase safety in potentially dangerous places on the roads. They are designed and installed on the roads to prevent any vehicle from getting outside the travelled way or from entering the opposite lane of the road. Barriers, which are used on European roads, have to undergo full scale crash tests according to the EN 1317 standards. Nowadays as a supplement to real crash tests, numerical simulations are commonly used. The work concerns the influence of position of the post or its absence on the crashworthiness of the cable barrier based on numerical study results.

This paper discuss the influence of selected factors on the performance of a concrete road barrier H2/W5/B. Modelling techniques of a concrete road safety system were briefly discussed. Comparison to the full scale crash test results has been shown. The concrete road safety barrier has been investigated for evaluation of the overall damage after collision under various initial conditions. The failure assessment criterion has been proposed and it was derived from a qualitative comparison of the numerical results with the full scale crash test data. Impact severity indexes have been calculated and discussed.

The paper concerns with the analysis of normative requirements pertaining to experimental setup of a crash test and its numerical modelling. An overview of parameters describing the collision of a vehicle with a road restraining system is presented. A short description of a concrete road safety barrier is presented. A brief description of numerical modelling procedures for crash tests is given as well. The parametric influence analysis is performed of the acceleration recording time on various crash test functionality parameters The simulations are carried out using LS-DYNA finite element code with a solver version R.8.1