large ground settlement brings great safety risk to both the tunnel
and its adjacent facilities.
The construction of a tunnel inevitably affects existing ground
stresses and hydro-geological conditions,whichwill induce ground settlement.
Suwansawat and Einstein [13] pointed out that a major problem
in evaluating the ground settlement was lack of extensive field
instrumentation data and relevant construction information. The proposed
DW provides an excellent data support to evaluate the ground