The challenge is to understand the idea behind a bridge

Employee portrait | Maarten van der Wateren

As a structural engineer, Maarten van der Wateren works on the replacement and renovation of civil engineering structures – bridges to be precise, which can pose a real puzzle.

A hundred and one factors

‘During my internship, I immersed myself in fatigue calculations; after graduating, I continued in that direction. The Netherlands has lots of old bridges and other infrastructure in need of maintenance. Steel rusts, concrete can crack, and rivets can come loose.

Through area studies and on-site inspections, we test the safety of bridges for Rijkswaterstaat. That’s quite a challenge sometimes, as some of these structures predate the Second World War. The trick is to understand the original idea behind a bridge. We then use a mathematical model to determine what needs to be done. A hundred and one factors influence the final decision.’

Algera Bridge

‘When I started at Witteveen+Bos, there was already a project waiting for me: the Algera Bridge. It consists of a truss bridge and a bascule bridge and is located in a busy corridor near Rotterdam. A lot of traffic passes over it. With the Algera Bridge, I was really thrown in at the deep end, which is typical of Witteveen+Bos. If you ask for it, your colleagues will support you, but you’re expected to do your own research first.

I covered all the steps – from A to Z. I didn’t just do the calculations, I also went to all the meetings with Rijkswaterstaat and the bridge’s administrator. It was an extremely instructive process. The conclusion of our assessment: the bridge’s main support structure is in good condition but the wooden deck of the bascule bridge needs replacing.’

Nerding around

‘Although every bridge is different, we try to digitalise our assessment processes as much as possible. Fatigue calculations, for example, are time-consuming and complex; Python or Excel can do them faster and better. Digitalisation helps us go a layer deeper, but the challenge is to make sure the results remain intelligible and understandable enough for everyone to work with them. Nerding around on the computer is fun, but I’m just as happy doing an on-site inspection. An A0-sized drawing can be rather abstract, but when you’re standing on the deck of a kilometre-long bridge, a project really comes to life.’