This chapter is divided into two sections. The first describes techniques of

improving and stabilizing the ground, with respect to both strength and

also permeability. The second describes the various lining techniques

commonly employed in tunnel construction. It should be noted that many

of the stabilization techniques and lining methods are intimately linked

with the tunnel construction methods described in Chapter 5, so the reader

is advised not to treat these chapters in isolation, but to treat both as part

of the tunnel construction process.