GEOTECHNICAL CHARACTERIZATION OF SHALLOW TUNNELS

Abstract

With increasing population all around the world, the available land for development of civil amenities such as transportation is reducing day by day. In such cases, underground structures become very essential to deal with such kind of problems. In most of the developing cities, underground mean of transportation is becoming very popular and efficient. But at the same time, excavating a tunnel in a city area is a mammoth task as most of the times it is at shallow depth involving the danger to the inhabitants of the cities in case of any failure of tunnels. Such kind of failure is always associated with huge loss of wealth to the government in the form of compensations to be paid if any property above the earth crust gets affected. This necessitates a well planned, geotechnical characterization of the earth crust before designing and excavating any of such kind of structures. In this thesis work a well planned series of tests have been conducted on rocks to reach geotechnical characterization of the ground for shallow tunnels. In this thesis a tunnel near Heidelberg named Necharaufertunnel has been considered and specimens have been drilled from different core holes. A brief description of the properties of the rock mass has been prepared and on that basis, using Hoek — Brown criteria, rock mass has been characterized. Thereafter, efforts have been made to propose types of tests to be essential and sufficient for design of shallow tunnels.