Abstract – Modern building technologies (for example
prestressed concrete to produce beams, floors, bridges, or
installation, testing and monitoring of ground anchors)
require the use of accurate force machines (hydraulic jacks).
One component of successful building works is a correct
and accurate calibration procedure of hydraulic jack for
tensioning cables or anchors. This article analyzes two
different calibration methods: By means of hollow load cell
and thread bar and calibration in the closed frame.