###### Abstract  
The estimation of damage in steel tendons is important for evaluating the remaining capacity of existing tensioned members. This research focuses on calculating Johnson-Cook (LC) model and damage parameters of high-strength steel material through quasi-static and dynamic uniaxial tests. Finite element analysis is used to replicate the experimental procedure, and through dynamic image correlation analysis, the numerical results accuracy is verified. In this investigation, it is found that the JC model can accurately replicate deformation and stress concentration under  
Once the state of corrosion in a tensioned member is verified, risk assessment analysis can be performed, and thus, the remaining capacity can be simulated with the aid of finite element (FE) tools. One of the most common tools used by researchers [8; 9; 10; 11] to evaluate the performance and characteristics of metals under coupled stress and high strain-rate conditions is the Johnson-Cook (JC) material model with damage [12] and it is currently one of the most widely incorporated models in commercial FE software packages, due to its ability to predict material behavior with accuracy and speed, and because it couples a flow stress model with strain rates, elevated temperatures as well as stress concentration conditions. [PERSON] et al. [13] performed an experimental investigation of seven high-strength steels in an effort to propose a modification to the traditional JC constitutive model. In their research, BH300, HSLA350, 440 W, HSS590, TRIPS90, DP600 and DP800 steel materials were used in uniaxial tensile tests with strain rates ranging from 0.005 s\({}^{-1}\) to 1000 s\({}^{-1}\), at normal environmental temperatures, as the heat-related material softening was not the primary objective of the research. Results were used to calibrate material parameters of the traditional JC constitutive model as well as for the evaluation of resulting differences between their proposed model, the traditional JC model, and the experimental data. From their research, it was found that from strain ranges of 2-15% and a tensile strength of 450-850 MPa, the proposed model had an average error of 2%, which is acceptable. [PERSON] et al. [14] investigated the mechanical response of two types of steel, Mild and DP590, in tension, at room temperature, using quasi-static and split Hopkinson bar techniques at strain rates ranging from 0.001 s\({}^{-1}\) to 1800 s\({}^{-1}\), and the resulting data were used to calculate the JC model parameters. It was found that for increasing strain rates, fracture strain as well as ultimate stress values increased in a similar manner approaching ultimate stress values of 1000 MPa. Finally, detailed JC material parameters were presented. From the performed literature investigation, it was clearly identified that to accurately model the fracture behavior of high-strength steels, proper material definition and model calibration is required. The data necessary for the aforementioned FE modeling need to be obtained through expensive and time-consuming experimental effort under both high strain rates and high-stress concentration conditions to accurately consider both damage initiation and progression parameters. For high-tensile-strength tendon material commonly used in Japanese infrastructure in general, readily available model constants are not available. In this work the overall behavior, including plastic deformation and the fracture characteristics of medium-carbon high-strength steel used in tensioned members, has been studied through extensive experimental analysis under quasi-static and medium strain-rate loading conditions as well as stress concentration through the implementation of the tensile testing of notched specimens. Failure parameters and material constants for the JC model under room temperature have been calculated through the analysis of experimental data.