Growth-curve characteristic of tunnel wall rock stable deformation

Through analysis to the tunnel monitoring measurement data of surrounding rock deformation near the tunnel portal, it is gained that the deformation curve of tunnel ground subsidence, arch crown settlement and perimeter deflection having obvious stage characteristic. At the same time, by nonlinear regression analysis to deformation curve of surrounding rock, it is also gained that the nonliear regression equations of “models of growth” which is fit for the deformation of surrounding rock, all these provide the basis for forcasting the deformation rule and final deformation of surrounding rock and for raising the informative tunnel construction level.