Three kinds of reinforced concrete prisms with different strength grades were placed in heavy saline soil for constant current accelerated test. The electrochemical workstation was used for nondestructive testing regularly. Weibull distribution was selected for reliability modeling. The shape parameters and scale parameters were estimated by median rank method, look up table method and maximum likelihood method. The results show that under the electrified environment of saline soil, the reliability curve shows the characteristics of three stages, the failure rate value is small in the early stage, and increases sharply in the later stage. Among the three kinds of parameter estimation methods, the scale parameter estimation value is less affected by the parameter estimation method, while the shape parameter value is more affected by the parameter estimation method. The shape parameter value obtained by the median rank method is the largest, the shape parameter value obtained by the look up table method is the smallest, and the shape parameter value obtained by the maximum likelihood method is between the look up table method and the look up table method.The parameters estimated by the four kinds of median rank are quite different, but the parameters estimated by the maximum likelihood method are very similar. Among the four methods of maximum likelihood method, bisection method and simple iteration method have more iteration times, while Newton Secant method and Stephenson iteration method have higher iteration efficiency due to the introduction of derivatives. The strength has a significant impact on the reliability of reinforced concrete. The higher the strength grade is, the smaller the density extremum is, the longer the failure interval is, and the smaller the failure ratio is.