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This paper addresses the problem of road safety regarding barrier placement as relative to the curb. A short summary of existing regulations is presented. Numerical simulations using the explicit finite element system Ls-Dyna are shown. In the analysis, variable distance between the barrier and the curb is assumed. The obtained result reveals that the distance has little impact on the working width of the barrier.

The paper presents proposals for the use of glass fiber reinforced polymer composites for the construction of engineering objects, known and commonly used in the shipbuilding industry. An example of a pedestrian footbridge was used in this case, which, despite the considerable thickness of the structural material, was made using infusion technology in one production cycle. The designed and produced footbridge span is durable, dynamically resistant, incombustible, easy to install and maintain, resistant to weather conditions and also aesthetically interesting. For footbridge production environmentally friendly PET foam core may be used. It may come from recycling of used plastic packages and which is produced with less energy consumption process and much less CO2 emission. The load bearing part of the structure (skin) is made of polymer laminate reinforced with glass fabrics (GFRP).

Development strategy for the port of Gdańsk assumes that , up to 2027, it will become the main transport centre in the Baltic Sea region. To this end , for many years work has been carried out to facilitate access to the port both by sea and land. One of the elements of extension of the port is the building of another terminal of Deepwater Container Terminal, Gdańsk. In this task, geotechnical operations aimed at appropriate preparation of subgrade for storage of containers and operation of cranes, have been especially important. Effectiveness of the assumed design solution of land-side girder for gantry crane has been verified by means of a technical monitoring system. This paper presents main elements of design the land-side girder of a new quay of the container terminal in Gdańsk, together with its computational analysis, as well as the results collected during a few months of observation, which have revealed real work of monitored elements.

The study raises the issues concerning the automatic system designed for the monitoring of movement of controlled points, located on the roof covering of the Forest Opera in Sopot. It presents the calculation algorithm proposed by authors. It takes into account the specific design and location of the test object. High forest stand makes it difficult to use distant reference points. Hence the reference points used to study the stability of the measuring position are located on the ground elements of the sixmeter-deep concrete foundations, from which the steel arches are derived to support the roof covering (membrane) of the Forest Opera. The tacheometer used in the measurements is located in the glass body placed on a special platform attached to the steel arcs. Measurements of horizontal directions, vertical angles and distances can be additionally subject to errors caused by the laser beam penetration through the glass. Dynamic changes of weather conditions, including the temperature and pressure also have a significant impact on the value of measurement errors, and thus the accuracy of the final determinations represented by the relevant covariance matrices. The estimated coordinates of the reference points, controlled points and tacheometer along with the corresponding covariance matrices obtained from the calculations in the various epochs are used to determine the significance of acquired movements. In case of the stability of reference points, the algorithm assumes the ability to study changes in the position of tacheometer in time, on the basis of measurements performed on these points.

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.

The article discusses modeling plastic hinges in reinforced concrete intermediate supports using finite elements methods. The ductility demand‐capacity method was used to determine the geometrical parameters of cross‐section plasticization zones, their ability to move and rotate, as well as their ductility. Due to the varied geometry and stiffness of the supports and their nonlinear behavior under dynamic load, this method was concluded to be imperfect. Therefore, an improved algorithm was proposed by determining the main parameters of plastic hinges depending on the degree of concrete degradation according to Lubliner's assumptions. The new algorithm has been implemented in the form of mathematical equations. It was subsequently used, at the structure design stage, to perform numerical calculations based on the finite element method. [ABSTRACT FROM AUTHOR]

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

Using the analytical format set forth in the first of these two companion papers, numerical simulations of a passive aerodynamic control method for suppression of the wind-induced instabilities of a very long span bridge are presented in this paper. At first, the aerodynamic stability of the uncontrolled system is discussed using a sectional model and full bridge model, respectively. Next, the efficiency of the proposed asymmetric and symmetric cable connection control systems is studied. Both systems offer similar maximum improvements in critical wind speed. The asymmetric cable connection system turns out to be very sensitive to horizontal motions, which strongly degrade its effectiveness. On the contrary, the symmetric cable connection system is not sensitive to horizontal motions, but its efficiency is limited by divergence. CE Database keywords: Aerodynamics; Bridges, span; Flutter; Passive control.

A passive aerodynamic control method for suppression of the wind-induced instabilities of a very long span bridge is presented in this paper. The control system consists of additional control flaps attached to the edges of the bridge deck. Control flap rotations are governed by prestressed springs and additional cables spanned between the control flaps and an auxiliary transverse beam supported by the main cables of the bridge. The rotational movement of the flaps is used to modify the aerodynamic forces acting on the deck and provides aerodynamic forces on the flaps used to stabilize the bridge. A time-domain formulation of self-excited forces for the whole three-dimensional suspension bridge model is obtained through a rational function approximation of the generalized Theodorsen function and implemented in the FEM formulation. This paper lays the theoretical groundwork for the one that follows. CE Database keywords: Aerodynamics; Bridges, span; Flutter; Passive control.

Horizontal curves are one of the elements of road infrastructure where statistically a relatively high number of accidents have been reported. In the last 10 years in Poland, approximately 10% of all road accidents happened on horizontal curves of roads and was responsible for approximately 14% of all fatalities on Polish roads. Thus, this issue is important and requires extensive research and proper road safety treatments. One possible measure that may contribute to improvement of safety on road curves may be barriers. The purpose of this work is to assess, with use of numerical simulations, the performance of the 4-cable barrier systems installed on horizontal road convex curves. The most important parameters for road safety barriers are presented including the effect of various impact velocities and the radiuses of the road curves. [ABSTRACT FROM AUTHOR]