Abstract
The squeezing and swelling deformation is a major threat in tunnel engineering. It can often cause serious damage to tunnel linings and produce high additional costs during tunnel construction and operation. The squeezing and swelling may result in a heave of the tunnel floor or the tunnel invert, or destruction of the lining or the invert, or uplift of the entire tunnel section. For an optical design of the tunnel and the countermeasures, it is necessary to predict the tunnel deformation. For that, it is necessary to understand the mechanical behaviour of squeezing and swelling rock as a basis.
In this paper, the relationship between swelling strain, pressure and time are introduced. And the strength reduction law is considered to this relation. In addition, this relationship is incorporated into elasto-plastic analysis considering the tension off by finite element method.
Consequently, this paper presents the results of a numerical back analysis of measured deformation in the ground and surface with a simple constitutive model using field observation and laboratory tests.
