The STO type axial force gauge, also known as the reaction force gauge, steel support axial force gauge, and steel support reaction force gauge, is a vibrating wire load sensor that can continuously measure the reaction force of the foundation on the superstructure, the axial force of steel supports, and the load during static pressure pile tests, etc. It features high resolution, strong anti-interference performance, sensitive response to concentrated loads, and good reliability of measured values. It can measure the reaction force of the foundation on the superstructure, the axial force of steel supports, and the load during static pressure pile experiments for a long time. If a temperature sensor is installed, the temperature at the installation point can be measured simultaneously