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• A novel approach for regional ionosphere grid model with high spatial-temporal resolution is suggested. • The results of the new model is analyzed at different disturb geomagnetic and solar conditions. • A comparative analysis between the results of new model, GIM, NeQuick and GPS-TEC is made. In this paper, a novel approach based on C1 finite element (FE) interpolation is used to construct a regional ionospheric grid model (RIGM) with high spatio-temporal resolution over Europe. The spatial resolution of the new model is 0.50 for a longitude and latitude and a temporal resolution is 15 min. Observations of 38 GPS stations at different days and seasons with different geomagnetic and solar activity conditions are used to evaluate the new method. All stations are used to discretize the whole domain of the problem into separate triangular patches using a Delaunay triangulation algorithm. In this case, GPS stations would be the vertices of the triangular patches. Also, the position of stations in sun-fixed coordinate system with coordinates of latitude and longitude are chosen in order to consider the temporal variations of vertical total electron content (VTEC). To model the behavior of VTEC in each triangular patch, a particular shape function is defined which is fitted to VTEC values at three vertices of each triangle while it satisfies C1 continuity of VTEC at the common edges of the adjacent triangles. The results of the new model are compared with the VTEC of GPS at 4 control stations as well as global ionosphere map (GIM) and NeQuick models. Statistical parameters, including correlation coefficient, root mean square error (RMSE), standard deviation and dVTEC = |VTEC GPS - VTEC model | have been used to evaluate the error of the models. In low geomagnetic activity (KP < 4), the average RMSE at 4 control stations for FE, GIM and NeQuick models are 0.89, 1.05 and 6.42 TECU, respectively, while in the high geomagnetic activity (KP > 4), they are 1.24, 1.68 and 7.62 TECU, respectively. For further analysis, the accuracy of three models in precise point positioning (PPP) has been also evaluated. In PPP method, there is an improvement of about 1–16 mm compared to GIM and NeQuick models at coordinate components of control stations in high geomagnetic activity. The results of the analysis performed in this paper show that the FE model has a very high capability and accuracy in regional VTEC modeling in high and low geomagnetic conditions. The regional accuracy of this model is higher than GIM and NeQuick models and therefore can be considered as a new model for the ionosphere. [ABSTRACT FROM AUTHOR]

• Paper describes a methodology that was successfully applied for the development of a temporary road traffic steel barrier in compliance with T1/W1 level according to EN 1317; • A simplified theoretical analysis of 178 barrier, laboratory test of three types of barrier connectors (for two types of barrier), explicit FEM modeling of four chosen barrier, and a full-scale crash test for final barrier are presented; • The stiffness of barrier connector was established based by laboratory barrier test (the FEM model was validated based on laboratory tests); • The chosen final barrier alternative passed the crash test for T1/W1 (TB21) containment level, performed by certified laboratory [35] , which proves that the presented procedure could be used successfully for traffic barrier development. Over a million people die in road crashes and tens of millions result injured or disabled each year, globally. Hence, there is a constant concern for improving the safety of the roads to protect road users, and those at the most risk, the road workers. Construction, maintenance, and utility work are constantly needed to ensure safety and functionality of roads and highways. Temporary road traffic barriers are used to separate passing traffic from the workspace and protect the workspace from an errant vehicle intrusion. Steel barriers are light, and their major advantage is rapid installation. These barriers are not anchored to the ground, and their behavior relies on the base-pavement friction, mass inertia, and stiffness of the system. The paper describes a methodology that was successfully applied for the development of a temporary road traffic steel barrier in compliance with the European specification EN 1317. The study included a simplified theoretical analysis of 178 barriers, static laboratory tests of three types of barrier connectors, development of explicit finite element models (EFEMs) of four selected barrier designs, and a full-scale crash test of the final barrier design. It is shown that static laboratory tests of complex connector systems can help to improve the design process and reduce the cost. The analysis and use of EFEMs was enough so that just a single full-scale crash test was sufficient for certification of the barrier design for use in Europe. The final barrier is compliant with the EN 1317–2 requirements for T1/W1 (TB21) containment level, which was confirmed by a full-scale crash test. [ABSTRACT FROM AUTHOR]

The fatigue life of orthotropic steel bridge decks in road bridges depends on the load effects exerted by heavy lorries. The contact surface of tyres is one of the important variables. Measurements described in the literature demonstrate that the actual tyre contact surfaces of today's traffic representative for Europe are shorter and slightly wider than the contact surface defined for the load model in the European standard for fatigue loads in bridges — EN 1991-2. This paper derives a new, realistic tyre contact surface to be used with the tyre loads in EN 1991-2, in such a way that the load effects for fatigue are realistically captured and that the required safety level is met. • Fatigue of orthotropic bridge decks depends on the lorry tyre contact surface. • The contact surface in Eurocode's Fatigue Load Model 4 is too long and narrow. • The width of the traction axle (tyre-to-tyre distance) in the load model is too large. • The finite element method is used to calibrate the contact surface in the load model. • Realistic tyre contacts are therein compared to a square contact with uniform stress. [ABSTRACT FROM AUTHOR]