Fifteen years of experience with the estimation of structural loadings acting on temporary supports of tunnels in Buenos Aires

Author(s): 
Alejo Sfriso and Jorge Laiún
Date: 
Thursday, May 15, 2014
First presented: 
World Tunnel Congress 2014
Type: 
Published paper
Category: 
Geotechnical

In 1998, shotcrete was used for the temporary support of a subway tunnel for the first time in Buenos Aires. The first author, consultant for the contractor, had developed a semiempirical method for the estimation of the structural support loads and used it to design the tunnel. The second author performed FEM models of the same tunnel and studied the effect of various variables, including construction stages and shotcrete thickness. By that time, a surprisingly good agreement was found between the structural loads obtained by the simple method and by the FEM models. 15 years later, both methods have been employed for the design of some 15km of tunnels. The agreement between the results given by the formulas and the numerical models was confirmed in most cases. In this paper, the derivation of the semi-empirical method is revisited; the results obtained for seven tunnels is compared to numerical estimates, and the differences are discussed.

Feature Author

Alejo Oscar Sfriso

Alejo O. Sfriso is a Principal Engineer with 25 years of experience in geotechnical engineering for infrastructure and mining works. He is an expert in the application of numerical methods for geotechnical design and analysis. In addition to his activity at SRK, he is the Director of AOSA - Geotechnical Laboratory, Professor of Soil Mechanics and Geology of the University of Buenos Aires, Vice President for South America of the International Society of Soil Mechanics and Geotechnical Engineering for the period 2017 - 2021, former Professor of Geotechnics at the National University of La Plata and former President of the Argentinean Society of Geotechnical Engineering.

Principal Consultant
PhD, Civil Engineer
SRK Buenos Aires
Jorge Laiun

Jorge has worked on problems of tunneling and underground works since 2004. He has participated in the geotechnical and structural design as well as in the optimization of construction procedures of tunnels for the underground network of Buenos Aires and Santiago. His expertise includes rock tunnels for mining in a variery of projects located in Argentina and Chile. Jorge has 13 years of experience and participation in the design of geotechnical and structural projects. He has focused his experience in the design using numerical methods applied to geotechnics.

Principal Consultant
Geotechnical & Structural Engineer
SRK Buenos Aires
SRK Latin America