Ankara Water Supply Project
TYLin designed the precast segments for two different types of tunnel lining for the Ankara Water Supply Project in Ankara, Turkey.
To provide potable water to the capital city of Ankara, the Ankara Water Supply Project diverts the Gerede River through a headrace tunnel that transfers the water to the area of the Çamlidere Dam. The tunnel is a free-flow conduit, 31.6 kilometers long with an inner diameter of 4.5 meters, which gives it a transport capacity of 40 cubic meters per second.
Due to geological conditions with the presence of medium to slightly weathered volcanic rocks (basalt, andesite, and volcanic breccia) and a ground overburden up to 600 meters, two different types of lining were foreseen. In addition, high inner water pressure was expected, so the waterproofing design was critical since the tunnel must be watertight up to 10 bar and, at the same time, guarantee water ingress into the tunnel at that pressure. We designed the lining with a pressure relief valve in the pea-gravel injection hole.
TYLin designed the precast segments for both ring lining types. Our team reviewed the segments’ formwork and waterproofing characteristics. We provided technical support in gasket selection, design, and pressure release valve specifications.
