Warm concrete in the chilly dawn



Concrete pouring operations resumed early on Wednesday 22 January in the southern corner of the Tokamak Pit.

Two large concrete pumps, one equipped with a 58-metre extensible arm (the largest available in France), were mobilized to fill a 500 square-metre area with specially formulated concrete produced in the nearby batching plant.

Operations began at 4:00 a.m. and continued for 10 hours. This was the second segment (out of 15) poured for the Tokamak Complex basemat, and one of three that will support the future ITER Diagnostics Building.

Special measures were set into place to counter the early morning cold, such as producing warm concrete in the batching plant (by heating the water and gravel) and using plastic sheeting as the work progressed to avoid too rapid cooling.

Hot air blowers were also activated once the pour was complete to regulate the drying process.

The complete Tokamak Complex basemat (1.5-metre-thick) is scheduled to be in place in July. Work will resume next week on the rebar installation in the central area of the Tokamak Pit.