What Does Jacking Force Mean?
Jacking force is the force applied by the hydraulic jacking system on the pipes for the purpose if installing it. Trenchless methods like auger boring and microtunneling use jacking systems that push the pipes through the soil from the jacking shaft to the reception shaft. This method allows for installation of small to large diameter pipes under roads, embankments, railway lines, rivers etc. without opening up trenches on the surface of the ground, minimizing disruption to vehicular and pedestrian traffic.
Trenchlesspedia Explains Jacking Force
During the pipe jacking operation hydraulic jacks located in the jacking shaft propels the pipe forward. As the installation progresses, the jacking force is transmitted from pipe to pipe. With new developments in the field of trenchless technology, there is an increase in the drive length that can be installed and improvement in the capacity of jacking force that can be applied. A thrust ring is used around the circumference of the pipe to distribute the jacking force evenly. To ensure even thrust the jacks are hydraulically interconnected. During the planning and design phase of a project it is important to calculate and predict the jacking force because that will dictate the location of the jacking shaft, placement of thrust block, jacking equipment, bearing capacity of the pipe, and need for intermediate jacking stations (IJS).