Langebro bridge - renovation of bascule span - Registration of internal condition of counterweights by nondestructive methods

Langebro is a bascule bridge in central Copenhagen, inaugurated in 1954. The counterweights of the bridge leaves consist of riveted steel boxes cast with concrete, which contain a large amount of scrap steel to increase the density and thus minimize the required size of the counterweights. The steel boxes are provided with internal steel bulkheads lengthwise and crosswise to increase rigidity and loadcarrying capacity. 

Under the influence of many years of seeping water, significant rust attacks have occurred on steel (both structural steel and embedded scrap) and degradation of concrete. Through thickness measurements (ultrasound and drilling holes) from the outside, a varying degree of crosssectional loss has been found on the outer steel plates due to corrosion, although not to a degree that currently gives rise to acute concern. The condition of the inner steel bulkheads is unknown, which is a problem as they are essential for loadcarrying capacity. 

The City of Copenhagen requests contact with companies that can use nondestructive methods to record the condition of internal steel structures and the aggregate concrete. The condition registration must be used to qualify the City’s assessment of the current need for renovation and the risk of unannounced breaks in the years leading up to a major renovation of the bascule leaves. There is no estimated date of publication of a contract notice within this procedure but as it is a mandatory field it is neccessary to set a date.

See attached document below for further description of the bridge, including drawings and illustrations. 

The documents can also be required by e-mail by contacting Gabriella Høgh via mail: v64m@kk.dk