Project Information: The work consists of the excavation and support, using top heading and benching, of three road tunnels with a trunk section of 21.1 m x 11.4 m. The total length of the excavation of the 3 tunnels is 595 m (240 m, 235 m, 120 m), with a longitudinal slope of between 0.3 to 3.0% and a maximum and minimum overburden of 40 m and 12 m respectively. The excavation will be done using conventional means. The supports used will be based on: Shotcrete, corrugated grout rock bolts, metallic trusses with IR type profile 203 x 59.6k kg/m. The final reinforced concrete lining will be installed to thickness of 40 cm. During this stage 6 false tunnels will be also be built, one for each tunnel mouth, resulting in a total of 245 m of false tunnels.
Province: State of Nayarit
- Cross section: 21.1 m x 11.4 m 192 m²
- Lenght: Mine Tunnels: 595 m, False Tunnels: 245 m
Overburden: 12-40 m
Method of Tunneling:
- Excavation by drilling and blasting or mechanical means support in accordance with NATM
Geology and Geotechnical Data: Volcanic rocks: rhyolitic ignimbrites, andesitic ignimbrites, rhyolitic breccias, andesitic breccias and andesitic lavas.
- Three-arm hydraulic drilling jumbo
- Shotcrete robot
- Excavator front bucket loader