55 km-long double-track line from Caracas south to Cua will have 26 tunnels, longest of which is Tazon at 7 km. Cross-section is arched with a width of 5.8 m and height of 6.8 m. Contractor is an Italian-Venezuelan consortium comprising Impregilo, Astaldi, Ghella, and Otaola Ingeniera. Concrete spraying using a dry mix is being undertaken around the 52 portals and along most of the embankment slopes by Trevi Cimentaciones using six Aliva AL 262.1 machines. Around 20 to 30 sq m/day of sprayed concrete is being laid at pumping distances of up to 150 m and at pressures of 5 to 7 bar. Completion scheduled 2003. Visit www.aliva.com January 2000.
