Authors:Anca Gido, Radu Bancila, and Edward Petzek
The paper describes the present methodology for assessment of safety of bridges and the remaining life of steel railway bridges. The majority of railway existing bridges are riveted, and this field has been researched in former studies, but there are also many welded bridges. Many bridges are still in operation after damages, several phases of repair and strengthening. The replacement of old bridges raises some technical and financial problems. This is the main reason why new method for assessment, based on fracture mechanics principles is researched.
Authors:Miklós Ifj. Ivanyi, Radu Bancila, and Miklós Ivany
Nowadays the most modern and economical bridges are designed as composite structures with orthotropic plates. In a traditionally designed composite bridge the trapezoidal, longitudinal stiffener is attached, welded to the cross girder web and to the bottom flange of the main girder. However in recent composite bridges with orthotropic plates designed by the UVATERV Co. the cross girder web and the trapezoidal, longitudinal stiffeners are not connected. This is a very important improvement, since in this way the amount of cutting and welding work can be reduced, however more importantly there is no need to consider the fatigue of the welds between the longitudinal stiffener and the cross girder web. On the other hand the disadvantage of this design that the plate-buckling phenomenon of the free edge must be taken into account. This paper studies the new orthotropic plate by the experimental tests.
Authors:Ramona Gabor, Edward Petzek, and Radu Bancila
In this paper the most relevant and an important aspect of the motorway crossings is presented. The composite bridges are, in comparison with steel bridges and concrete bridges, the most proper solution for motorway crossings because they are efficient, the erection time is shorter and the “in situ” operations can be minimized. The attention is focused on general design criteria of these crossings. Fabrication and erection methods have a big influence on the detailed design of the steel structure. The supporting steel members must be designed so that they do not interfere with the placing of concrete slab.
Authors:Silvia Rominu, Oana Ionita, and Radu Bancila
The concept of structures reliability conditions besides safety also must provide adequate durability and service life. According to EN 1990 reliability should be considered as its ability to fulfil the specific requirements, including the designed working (service) life. The structure and structural members should be designed executed and maintained in such a way that during their intended life, with appropriate degrees of reliability and in economic way, they will have adequate structural resistance, serviceability, durability and robustness.