Concrete collapse

Name: Eva Lantsoght (26)

Nationality: Belgian
Supervisors: Professor Joost Walraven and Dr Cor van der Veen (Concrete Structures section; Civil Engineering faculty)
Subject: Shear capacity of reinforced concrete slabs under concentrated loads close to the support
Thesis defence: In two years

“During the last two years I’ve been testing big concrete slabs. In 127 tests, I’ve looked at how cracks and failures occur. In the laboratory, I’ve put loads on 5 x 2.5 meter slabs, 30 centimetres thick, until they collapsed. It’s very spectacular to do the tests, because all the materials I use are so big.

The testing is part of my research on how forces flow in concrete slabs that are used in bridges. I especially focus on loads close to the supports. In the Netherlands, many slab bridges were constructed in the 1970s, when many highways were built. However, it’s not yet known how the slabs behave. But due to the increased traffic volumes and the European Union’s new concrete design codes, it is necessary to know the behaviour of bridges. Together with colleagues in my group, we conduct research to fill in (some of) the gaps. We try to get to know what the real capacity of the bridges is.

The concrete slabs I use during the tests are scale models; they are half as big as the ones that are used in bridges. I love to do the tests. When I first started, I feared that doing a PhD would be a bit boring, but it hasn’t been thus far. No test is the same: every time something different occurs. I use a crack width comparator, which is the size of a business card, to measure the crack widths. I then record the test results in a lab book. I will analyse my test results over the course of the next two years. I’m excited to see the results.

Since last year I’ve been writing a blog about my research and life in the laboratory. I started it because I wanted to show others what’s going on in my life as a PhD student. And when I look back in a couple of years and read my blog, I will know exactly what I did. The blog is sort of like the lab book I also keep during the testing.

In my blogs, for instance, I write about how to handle large amounts of literature and how to write an abstract in 30 minutes. To be a PhD student is to learn many new things. As an engineer, one is always prepared for all challenges. I have therefore taken extra courses and write about things I come across and what I’ve learned.”