18 - 03 - 2015
Kelly Formwork (UK) Ltd broke the current UK concrete pumping record for a single line push on the C310 Thames Tunnel project. The company teamed up Schwing Stetter UK to help and assist on the project.
This task involved pumping concrete an extremely long distance, from a standing point outside of the tunnel, to the finish point 1.31km away at the end of the tunnel. The companies experience in pumping concrete was vast, but pumping a distance as far as 1.31km was a complete unknown, so to they took a risk is an understatement.
The concrete line consisted of 437 high pressure concrete pipes , at 3m in length, with the total volume of concrete at any one time in the line itself just over 16m3 (over 38 tonne in weight).
Another factor that made the concreting process so unique was that they were adding “dry” concrete pipes as they were progressing throughout each slab pour, rather than the usual, industry wide method of removing pipes.
This introduces a whole new risk as pumping concrete into a dry pipe can cause blockages. With a concrete pipeline of this scale, and the addition of dry pipes, all aspects of the job had to run like clockwork ensuring blockages didn’t occur, and in an extreme case, the entire pipeline to go off.