Shafts made of segments with an internal diameter of 4.64 m
It is a shaft made of 6 rings, each with a height of 1.5 metres. There are 3 segments of 120º forming an arch per ring. Every other ring segment is installed 60º rotated off the segment underneath.
Structural height is 10.5 m, wall thickness (enlargeable) is 20 cm.
Hoop reinforcement is φ 8/150, circumferential reinforcement is φ 8/300. In the vertical edge an 80 mm-wide and 35 mm deep (measured on the surface) groove is made which is filled with “Mapefil” non-shrink grout to glue the elements as well as to make the joints impermeable to water.