Selected Projects

Rohrbach Bridge along highway A8, near Stuttgart

Bridge Uttrichshausen on the A7 Fulda-Würzburg

Highway crossing structure Oberelsungen

Carola-Bridge in Dresden

Car Park 'Lower Gate' – Bayreuth

Pfaffenstein-Bridge in Regensburg

St. Mary's Car Park – Colchester, Essex, UK

Kurgarten-Bridge in Nuremberg

Rohrbach Bridge along highway A8, near Stuttgart

With a qualified, non-destructive corrosion survey at the bottom side of the bridge deck (under traffic) a considerable corrosion problem of the tendons could be excluded. This information made a reconstruction of the bridge possible, in which it should be expanded from 3 to 4 lanes and delivered an important feasibility criterion in an early stage of planning. The project will be presented on the 18th Dresden Bridge Construction Symposium together with the consultancy Prof. Dr.-Ing. Heinrich Bechert + Partner, Stuttgart

Bridge Uttrichshausen on the A7 Fulda-Würzburg

Because of a leaking drainage system much chloride containing water run over a longer period into the box girders of the bridge. This was generating high chloride concentrations in the box floor - up to 3 wt-% of the cement mass. Within a pilot application for the federal state of Hessen, CITec was doing an electrochemical Chloride Extraction on 2 box girders. The repair areas had a size of ca. 60 and 75 m².
Within 90 days of application on the 60 sqm area, ca. 75% of the initial chloride content could be removed. In total, 6.6 kg of Chloride were determined in the ion exchanger of the CombinationElectrodes. This equals an average removal effect of 196 g NaCl per sqm concrete surface.

The second, 75 sqm large area has been prepared perfectly within just 35 days for an extended repair and protection of the whole box girder. Up to 63 % of the initial chloride were removed from highly affected areas and the corrosion activity could be taken down.

Highway crossing structure Oberelsungen

The splash zone of the center column of this bridge situated on the highway A44 between Dortmund and Kassel has been rehabilitated by the electrochemical chloride extraction within 6 weeks. For a long-term protection the surface of the column has been treated additionally with a hydrophobic cream application afterwards. The concrete surface has not been affected by the CE treatment (see picture on the right side).

Carola-Bridge in Dresden

With a survey of condition in the box girder of this bridge across the river Elbe corrosion active and corrosion endangered areas could be identified, caused by chloride ingress. Partly a high chloride concentration was obtained – also in areas with tendons. With a multi-stage ECE application, in total about 5.6 kg of chloride could be removed non-destructively from a 78 sqm concrete area, that was covered by a mineral coating; the corrosion activity has been eliminated securely. In another section, an electrochemical re-alkalization of 204 sqm carbonated concrete has been executed successfully.

Car Park 'Lower Gate' – Bayreuth

After conducting non-destructive corrosion measurements on the structure, we have been running a referential application for the ECE from wall and column bottom areas. More than 2.2 kg of chloride were removed from 12.5 sqm concrete surface. There were no use restrictions in the garage area.

Installation in the Car Park 'Lower Gate'

Pfaffenstein-Bridge in Regensburg

For preparing activities of maintenance and conversion, we conducted a non-destructive survey of the box-girder sections in which the spread-out of chloride in the concrete and resulting corrosion activity of the reinforcement has been defined. From 6 areas of the box girder floor slab (200 sqm in total, containing increased chloride and being corrosion active), more than 25 kg of chloride were removed by a chloride extraction treatment, which corresponds an amount of 41 kg NaCl that has penetrated the concrete originally.

St. Mary's Car Park – Colchester, Essex, UK

For planning and selecting of repair options we did special corrosion measurements (polarization measurements, galvanostatic pulse measurements) on the floor slabs of the car park on behalf of the Colchester Borough Council and in association with MG Associates Ltd. The amount of corrosion activity could be determined exactly.

Kurgarten-Bridge in Nuremberg

During a bridge inspection according to DIN 1076 corrosion damages on the structure have been investigated and evaluated. On this occasion, extended corrosion measurements (polarization measurements, galvanostatic pulse measurements) have been executed.

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