Ring bores for Prague

摘要

Contractors Skanska and Subterra are well advanced with excavation work on the 1.7km long twin bores in project 513 for the outer ring road at Prague.rnSkanska has excavated more than two-thirds of the larger (three lane), right tube for uphill traffic. Subterra will complete the balance of the tunnelling on the tube. For the other, smaller (two lane) tunnel for downhill traffic the contractors are equally splitting the work. Tunnelling is round-the-clock, six days per week.rnBoth contractors are using Atlas Copco boomers for the heading excavations - Skanksa is employing Rocket Boomer E2Cs and non-electronic 352s, and Subterra has also Rocket Boomer E2Cs as well as L2C drill rigs. For the bench works there are Atlas Copco hydraulic breaker - MB 700 and MB 2,500.