Materials Used to Build the Channel Tunnel

Primary Materials

• Precast Concrete Segments: Cast in France, each ~2.5 m wide, 6.5 m tall, 12 m long, reinforced with steel rebar, assembled like Lego blocks.
• Steel Tunnel Linings: ~10 mm thick steel welded inside segments for strength and waterproofing.
• Grout Filling: Cement-water mixture fills gaps between concrete and steel, sealing joints.
• Bitumen Coating: Applied to steel linings for corrosion protection and additional waterproofing.

Additional Materials

Sand, gravel, concrete, brick, stone, glass, electrical wiring, plumbing, ventilation ducts, and fire safety systems were also used.