The Inspection and evaluation of the bearings, stoppers, shear-keys, and viscous dampers of Tsakona arch steel bridge in Korinthos-Tripoli-Kalamata Highway (Southern Greece) has been accomplished by HiSCS Inspectors.

The Tsakona arch bridge is one of the world’s longest multi-span arch bridges. It crosses the Tsakona valley bridging a dangerous location with landslides phenomena often occurred the last decades.

It has a total length of 390m, consists of three (3) spans of length 75m – 55m and 260m respectively. The first and second spans form a prestressed reinforced concrete box section, while the third span of 260m long is a steel composite deck suspended by two steel arches trough wire ropes.

The prestressed deck of the bridge rests on the abutment on two (2) free-sliding elastomeric bearings (800x800mm plan area). The shear forces are transmitted through a shear-key device (of 6000KN/±160mm capacity) movable along the longitudinal axis. The deck is monolithically connected on the V shaped pier.

The steel arches are seated on four (4) elastomeric bearings (900x900mm plan area) capable to bear an uplift load of 250KN. In addition, the deck is connected through eight (8) hydraulic viscous dampers with capacity 500KN/±200mm, oriented in the longitudinal and transverse direction of the bridge.

The combination of elastomeric bearings and viscous dampers is one of the best design approaches to secure the seismic protection of a structure.

All inspected elements have been checked about functionality (residual sliding/deformation capacity, rotations/inclination, defects etc.) and a relevant evaluation report has been issued. A special inspection software has been used so as to speed-up the site works.

The inspected elements were manufactured and installed in 2009-2010. 

Supporters of a robust inspection and maintenance regime in all structures we are pleased to see that this mentality spreads among the Engineers and Authorities. Inspection and maintenance is considered as a necessity in nowadays.