ROTTERDAM - The Erasmus Bridge in the center of Rotterdam is immediately closed to all traffic, after the bridge started shaking in the wind. Several people who were walking on the bridge at the time fled from the bridge. Yet those people were not in danger, says the municipality of Rotterdam.

By the southwest wind, power 6 tot 7, the cables of the new bridge started to vibrate. “It looks like a guitar”, said Radio Rijnmond reporter Jack Kerklaan with a laugh. Nevertheless, the municipality emphasizes that there is no damage to the bridge and that there is no danger of collapsing.

In the dagvantoen podcast there was a look back at the 'teething problems'’ from the Erasmus Bridge. Vanaf 17:00

Initially there was a fear that the bridge had become detached in its entirety, but that was not the case. Due to the moving cables, the bridge deck partly moved along and you could feel it. “It is an integrated whole. When something starts to vibrate, everything vibrates”, says H. Dieterman from TU Delft across the bridge in Trouw. “All bridges are rocking, that how it's supposed to be, but it shouldn't be too bad. On a bridge that shakes too much, people don't feel safe anymore. The bridge also wears faster.”

The flapping ropes have now been attached with nylon ropes to prevent swishing. Municipal works have also started an inspection. An hour after the closure, the ships were allowed to pass under the bridge again. It is not clear when road traffic will be able to use the bridge again.

Shock absorbers

According to engineer Hardenberg, who supervised the construction of the Willemsbrug, late 70s, says in Trouw that emergency plans were ready if the cables were to vibrate, but that those emergency plans were never used. “They interconnected the cables”, he explains in the newspaper. “That dampens the vibrations. In France, they also later installed shock absorbers on a large suspension bridge over the Seine.

The expectation is that the shock absorbers of the tethers have not yet been adjusted tight enough, but that is not certain.



Past issues

The closure of the bridge comes exactly two months after the opening by Queen Beatrix. Since then there have been more problems, such as asphalt loosening on the bridge and problems with the barriers. Since then, the bridge under Rotterdam has been given the predicate 'worry child' and today's problems will not help with that.

The Erasmus Bridge cost 365 million guilders and was built in about a year.


Hoe ging het verder?

Later it turned out that the pylon, the bridge deck and fronts have never been tested in a wind tunnel.

The vibration in the cables was caused by the rain. Because of the layer of water on the cables, the cables started to resonate in the wind.

New shock absorbers have been installed to dampen the vibrations.

Sources:

Radio Rijnmond – 04-11-1996 – Post in the Afternoon

Trouw – 05-11-1996 – Builders do not believe that Erasmus Bridge is about to collapse

De Volkskrant – 05-11-1996 – Erasmus Bridge can't stand a strong breeze

De Volkskrant – 06-11-1996 – 'Swabbing Erasmus Bridge is perfectly normal’

Trouw – 07-11-1996 – Erasmus Bridge victim of blind spot designers

Author: Dave Datema

published: 04-11-2021

story number: 241