2 x 1,505 m Silver forest tunnel under construction in Moscow by Mosmetrostroy using the Herrenknecht TBM previously used for the Lefortovo tunnel. It is a 2,600 t, 63 m-long mixshield, outer diameter 14.2 m, total installed main drive power of 3,200 kW + 315 kW for central cutter wheel, total installed power of 5,196 kVA and maximum thrust force of 120,000 kN. Geology is sand (nearly 600 m), then shifting to clay with inclusions of limestone and rocks up to 1 m. Concrete lining rings consisting of eight segments plus key, each ring is 2,000 m in width. Separation plant and slurry pipes by MS of France. Length of tunnel already excavated to date is 1,238 m with expected breakthrough date on first tunnel scheduled for 15th March. Visit www.herrenknecht.com, www.m-s.fr and www.metrostroy.ru 07/05.
