As part of a nuclear project out of Scotland, engineers adopt an innovative new concrete building tool they plan to use in floors, walls, and ceilings, all without rebar. Builders expect Steel Bricks, part of GE Hitachi’s (GEH’s) BWRX-300 small modular reactor (SMR) plant, to reduce the required labor significantly.
Says Brian Johnson, vice president and BWRX-300 product director with GEH, “This design actually is expected to have no rebar in the nuclear island, which, compared to existing nuclear plant designs, dramatically reduces the amount of construction labor in the field.”
The Steel Bricks system is made by folding two pre-cut steel plates into L-shaped sections and joining them to form a U shape. Builders place the U shapes side by side in a traditional brick pattern and infill the structures with concrete.
Dr. Stewart Gallocher, founding director of Modular Wall Systems (MWS), believes the system’s unique design makes it ideal for SMR construction. In a statement, he said: “The Steel Bricks system is a ‘first-of-a-kind concept in the fast-emerging world of steel composite construction. It provides not just the walls and suspended floors or roofs in steel composite; but, most importantly, a basemat; this takes away the need for conventional foundations, eliminating the traditional Achilles Heel of this form of construction, which are the weak points of the base mat to wall connection.
“This is all being done to make the small modular reactor safer by building it below ground level. The reactor will be set using very experienced tunneling techniques in basically a vertical boring in the dirt and then placing these SC modules in that boring. Use of the embedded structure also allows us to take advantage of the surrounding soil to add structural strength to the reactor containment module, and that again allows us to provide a cost-competitive, easily constructible solution.”
Brian Johnson says the Steel Bricks lower the human resources needed with traditionally tied rebar, making manufacturing more manageable. “It’s a much simpler design from a manufacturability standpoint than traditional steel composite structures.”
Steel bricks, an innovation from Modular Wall Systems, offer more straightforward construction with less required labor. Additionally, builders anticipate that the sub-surface structure will increase safety in the future use of its GE Hitachi BWRX-300 nuclear reactor.