<p>The increased use of underground space for transportation systems and the increasing complexity and constraints of constructing and maintaining above ground transportation infrastructure have prompted the need to develop this technical manual. This FHWA ...

<p>This paper describes the methods that can be used to optimize the design of tunnels using a combination of reinforcement and support methods. Particular attention is given to tunnels in very weak rock or soil in which large deformations can occur. Two case ...

An example is shown how systematic application of engineering geological data and construction aspects can be combined to assess the amount of rock support and tunneling progress for a tunnel.