EVOLUTION OF CONSTRUCTION PROCEDURES FOR METRO STATIONS IN BUENOS AIRES, ARGENTINA (original) (raw)
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Large Caverns for Metro Stations in Buenos Aires
Buenos Aires Metro Line H, in Argentina runs N-S, at the west side of the city's downtown area. An extension of the line started in 2011. A TBM tunnel and one cut&cover station will be built southbound in estuary soft holocene soils; CTM (conventional tunneling method) tunnel and three cavern stations are being built northbound in stiff cemented silts and clays. The experience accumulated in the last fifteen years has allowed for continuous advancements in the construction methodologies used for tunnels and underground caverns in stiff soils. Nowadays, the Line H northbound caverns-approximately 135m long and with a +200m 2 face-are being excavated full face with excellent performance, far better than previous experiences where more conservative, staggered excavation procedures were employed. In this paper, the evolution of the CTM techniques in Buenos Aires´s big metro caverns is reviewed; the advanges and disadvantages of the changes in procedures are discussed and different optimization alternatives awaiting to be developed are described.
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Bogotá, the capital city of Colombia, has experienced a critical situation regarding its public transport and road network condition. Unfortunately, the city has lacked an analytical long-term evaluation with regard to transport planning and infrastructure that is able to meet the growing demand. The metro system has been planned for more than half a century, and the existing soil investigations have not been fully used to evaluate the feasibility of building a metro in Bogotá’s subsoil. In order to estimate the construction viability of an underground system in the city, the authors studied the ground conditions along the alignment of Metro Line 1, as proposed in 2014. This research brought forward the stratigraphic profile of the first 6,6 km of the alignment. The ground displacements induced by tunneling were estimated by means of a finite element analysis, and the results are presented in this paper along with their significance. The results forecast surface settlements lower th...
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The current design practice of urban tunnels in soil as perceived in Brazil is reviewed and discussed. The review is based on answers to a questionnaire sent in 2006 to practitioners involved in the design or in the design supervision oftunnel projects. The results ofthis investigation are carefully considered to identify trends and needs for development.
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