Cycling infrastructure is ubiquitous in the Netherlands. There isn’t a place in the country that you cannot safely reach by bicycle. That doesn’t mean the quality of the nationwide cycling network is excellent everywhere, there certainly are municipalities which could do better. On the other hand it also means that you can sometimes be very surprised when you find incredibly good and expensive pieces of cycling infrastructure in tiny villages. The huge cycling bridge over the river Donge, connecting the tiny towns of Raamsdonksveer and Geertruidenberg (both in the same municipality by the latter name) is an example of such an iconic piece of infrastructure that you wouldn’t expect in a municipality of just 22,000 people.
You have probably never heard of Geertruidenberg, but it used to be a fortified city. It was granted certain trading rights in 1213 by the counts of Holland, that it was part of at the time. The borders have changed since then, which means that Geertruidenberg is no longer in Holland, but in the province of Noord-Brabant. Raamsdonksveer became part of the municipality in 1997. More people live in that part of the municipality, but it kept the name of the historic city of Geertruidenberg. In 2007, the bright white bridge, with a single pylon, over 42 metres tall, was created as an iconic connection between the two towns that had historically never had any connection.
The slender cable-stayed bridge, with a main span of 86 metres, is part steel, part concrete. Those very different materials are seamlessly and invisibly connected by the clever design. When the development of a new housing area between the two towns got them physically closer, the bridge was designed to tie the town cores together even more. It was named after Willem Letschert who was mayor at the time the towns merged. He had died at the very young age of 45. His widow and two children officially opened the bridge late 2007.
The municipality was so proud of the bridge that it was entered in the competition of the “Steel Award” in 2008. I could not find if the bridge was nominated, but it did not win the award. In the bid-book the bridge was described as follows:
An iconic bridge for walking and cycling connects the rustic landscape of the fortress in Geertruidenberg and the housing estate Rivierzicht-zuid in Raamsdonksveer.
The piece of infrastructure emphasizes the line of sight between the main squares in Geertruidenberg and Raamsdonksveer. With the realization of the riverside residential area Dongeburgh, the village centres on both sides of the river Donge have been directed to each other. In the development vision, the municipality has strived to create an exceptional bridge, a landmark that would physically bring the two cores together. Symbolism that took shape with the cables of the cable-stayed bridge stretched tight between the two river shores. In addition, there was a tension between this ambition and the maximum construction budget: one and a half million euros.
Slender shapes were central to the design of the bridge. The slenderness has been emphasized by increasing the main span to 86 meters. In addition, the construction height of the bridge deck has been reduced by a construction with closed cell shafts. As a result, the construction height has been reduced by 30%. The rounded side of the bridge deck makes the bridge look extra slim. The diameter of the pylon in each cross-section has been adjusted to the capacity requirement, so that the most optimal shape has been chosen here too. On the Geertruidenberg side, the cable-stayed bridge is provided with three static concrete abutment bridges and two concrete cable-stayed bridge spans. The short rear spans are constructed with precast concrete girders with a compression layer to balance the weight of the main span. The outer prefab girders are attached edge girders with the same round shape as the steel bridge. The pylon is passed through a recess in the deck and kept completely clear of the deck. The pylon has a hinged support at the bottom. The support is raised on a concrete base to remain above the waterline in case of high water. The pylon’s foundation is completely submerged so that the slim pylon shape lifts itself out of the water, as it were. In order to strive for as much uniformity as possible with the pylon, the other supporting pillars are designed as slender round single columns. The large span and slender construction make the construction dynamically sensitive. For financial reasons, we did not opt for external damping, but for as many improvements as possible within the construction itself. The steel cables were designed in such a way that no movement interactions with the bridge deck occur. An elastic damping coupling has been applied to the bridge railing to limit any cable movements. During the implementation, a large sheet pile wall was used on the Geertruidenberg side in the river, within which all piers could be realized in the dry. The concrete was poured in situ, except for the prefab bridge deck girders. At the location of the cable anchors, steel pipes are incorporated in the concrete column table to transfer the forces into the slender concrete body. Because stranded cables are difficult to adjust, an exchangeable link plate was chosen. The steel span was prefabricated in three parts and placed on two temporary supports in the river and welded on site. A monolithic connection has been realized at the transition between steel and concrete. The pylon, more than 42 meters tall, was brought to the site in its full length. Placing it in one piece was instantly giving the bridge its shape in a glorious way.
In my videos you can get an idea of what this bridge looks like and feels like to use. It is great that the municipality chose this bridge as a lasting memory of the merger of the two towns. Because it is a very practical monument used by many on a daily basis.