Objective  The fan foundation with prestressed anchor bolt type connection design is the mainstream design at present. The mechanical characteristic of the foundation connected by prestressed anchor bolt is a kind of circular load. There is no detailed analysis data to refer to under such mechanical characteristics. The designers often rely on finite element analysis to analyze the structural safety here, but it takes a longer time. This paper aims to quickly calculate the stress value of the core region of the foundation

  Method  Based on the Mohr-Coulomb theory and elastic mechanics theory, a set of vertical stress calculation formula suitable for the design of the core area of fan foundation was derived in this paper, and compared and verified with the fine finite element analysis results.

  Results  Comparative results indicate that the formulas derived in this paper demonstrate good accuracy and reliability.

  Conclusion  The derived formula presented in this paper can be used as the basis of fan foundation reinforcement design and reference for engineering design.