The probability characteristics of the heliostat support column base shear are discussed, and related methods are used to determine whether the base shear is conformed to the Gaussian distribution under all working conditions. Then, three kinds of peak estimating methods are selected to calculate the peak base shear, and results are compared. It is found that the Generalized Pareto Distribution (GPD) method is the most suitable for calculating the peak value of the heliostat support column base shear. Finally, the variation law of peak values of heliostat support column base shear is obtained and the variation law of peak and mean base shear are compared. The judgment criterion of whether the heliostat support column base shear is conformed to the Gaussian distribution is obtained, Gaussian and Non-Gaussian regions are divided. The peak value of the heliostat support column base shear which is calculated by the GPD method and met the specified guarantee rate has high accuracy. It can be met the needs of engineering application. The analysis of the variation law of peak values of heliostat support column base shear can be a reference for engineering design and scientific research. (c) 2020 Elsevier Ltd. All rights reserved.