ABSTRACT
The Northern Lock ('Noordersluis', 1924–1928) was one of the world’s largest pre-World War II infrastructural works. It was part of a series of enhancements of the North Sea Canal, connecting Amsterdam to the sea. It was designed by a team of engineers led by Johannes Ringers, including J.P. Josephus Jitta, C. Tellegen, F.E. Mulder and B. Peiser. The challenges faced were at the frontier of 1920s concrete technology: development of concrete resistant to water penetration and cements with low heat development and good seawater resistance as Portland cement was not durable in marine environments. The latter were found in blast furnace slag cements and trass additions. Usage of blast furnace slag cement was novel for the Netherlands and a violation of contemporary regulations. Its bold introduction by Ringers and colleagues is a lasting legacy of the Northern Lock, resulting in the widespread use of ground granulated blast furnace slag cements with high slag contents (CEM III/A with > 50%, CEM III/B with ca. 70–72% slag) for major infrastructural works in the Netherlands, with evident durability and sustainability gains.
