Hydraulic Tunnel for the Renace IV Hydro Power Project

Project Information: The project involves the excavation and support of a 3.50 m. x 4.20 m hydraulic tunnel with rectangular-vaulted cross section. The tunnel length is 3,401 m. with a 0.015% longitudinal gradient, a maximum cap of 385 m and a minimum cap of 8 m. Excavation shall be performed using conventional methods. The support system will consist of: shotcrete, expansion bolts and grouted corrugated sheathing, 6×15 W-type metal trusses and THN-16.5 sliding metal trusses.

Country: Guatemala

Province: Departamento Alta Verapaz

Place: San Pedro de Carchá

Geometry:

  • Sección: 3.5 x 4.2 m. 16 m²
  • Longitud: 3,401 m

Overburden: 8 – 385 m

Method of Tunneling:

  • Excavation by drill and blast or mechanical means
  • NATM support systems

Geology and Geotechnical Data:

  • Karstic limestone intercalated with marl

Tunnel Equipment:

  • Hydraulic two-boom boring jumbo
  • Shotcrete robot
  • Backhoe
  • Telescoping handlers
  • Trucks and low-profile loaders