HiSCS has recently performed the jacking and lifting of the Corinthos canal (Isthmus) bridge, an iconic and of strategic importance cantilevered vehicular bridge.
The bridge has been erected back in 1996. It consists of 2 branches, each having 3 spans (max span 110m) and a total length of 190m. The superstructure is supported at piers by free sliding pot having a vertical capacity of 82000KN and an allowable sliding in both longitudinal and transversal direction of ±400mm.
The basic dimensions of these bearings were 2020x2020x219mm, weighing more than 4.5 tons each.
Among other reasons, the recent monitoring studies did reveal that the bearings were likely to not slide at all (stacked). In addition, their sliding material is considered obsolete not covered by the modern EN standards. The seismic isolation design specified the use of new sliding anti-seismic bearings having a curved sliding surface (commonly known as Friction Pendulum Systems – FPS). These devices consist of a concave slider (top plate) whose radius of curvature imposes the period of oscillation and accommodates the horizontal displacement and the lower plate with a secondary concave sliding surface that permits rotation. The bearing behaves like a pendulum because of the re-centering mechanisms that keep the superstructure almost centered after an earthquake. The new bearings have a vertical capacity of 70000ΚΝ and sliding allowance in both directions ±400mm. Their basic dimensions were 1890x1890x220mm, with weight about 3.2 tons each.
Eight jacks’ of 1000 tons lifting capacity each with locking rings and spherical heads were used considering that the bridge during lifting process should always remain open to traffic < 26 tons vehicles without the use of temporary support (lack of space).
HiSCS executed all stages of jacking-lifting and replacement works in all 4 piers. The average time per jacking location was about 15 working days.
Considering the existing pot and new anti-seismic surface sliders among the biggest and heaviest bearings in the world as well as the strategic importance of this bridge, HiSCS faced challenges beyond any previous experience. It is well known that the lifting and jacking of any bridge requires a unique approach and inventiveness with on-the-spot decisions and concepts affecting significantly the completion of work.
For more details about this project follow the link: https://hiscs.gr/wp-content/uploads/2026/07/Jacking-Lifting-of-Corinthos-Canal-Bridge.pdf
