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The repair of structural elements for the prestressing of reinforced concrete is necessary when existing prestressing wires are damaged or after a certain period of time. The objective of this paper is to describe the methodology for the life assessment of corroded prestressing wires, sampled from prestressed concrete elements after a few decades of use. The aim of the presented research was to determine the real properties of corroded wire in terms of the evaluation of remaining load capacity using the Theory of Critical Distances (TCD). The methodology also includes spatial 3D characterization of corroded surfaces, determination of mechanical properties, and Finite Element Analysis (FEA) of a model of wire with corrosion pits. The final goal of the presented methodology is to enable more efficient evaluation of repair range and options for the elements of mechanical prestressing systems within various structures. The results and conclusions indicate that the developed methodology, based on the interdisciplinary approach and implementation of state-of-the-art methods, has a high applicability potential for both static and fatigue fracture prediction in the case of prestressed wires. The proposed method has a huge potential for simple and fast prediction of the life assessment of engineering structures, particularly for damaged elements with arbitrary geometry features

Major function of railway vehicles absorbers is to absorb energy through controlled deformation during frontal rail vehicle collisions. The results presented and discussed in this paper is a part of the research of one particular type of absorber consist of a thin-walled seamless tube and conical mandrel. The influence of the groove, which occurred during cold worked tube manufacturing, on the behavior and energy absorption of this type of shock absorber is analyzed. The coupled nonlinear Finite Element Analysis is used for calculation of stress-strain state and plastic deformation work/volume of tube absorbers with defects. The results of the research presented in this paper show that the grooves on outer surface of expansion tubes in some cases can be beneficial due to strain hardening process in root of stress concentrator i.e. defect. The beneficial effect of grooves is proven by simulation in which is obvious that the energy absorbed level could be higher on expansion tube with grooves.