Time-dependent deformations of rock are important factors for the design and construction of tunnels in the rock masses with time-dependent strength and deformation properties. Therefore, determination of the displacement and the stable time of tunnels is an indispensable task in geotechnical engineering, especially the design and construction of underground structures.
However, in some types of rock masses, tunnel displacement may increase for months or years after excavation owing to the rheological behavior of the surrounding rock masses, which greatly influences the selection of an initial tunnel support system, excavation layout, and determination of its load-carrying capacity.
Therefore, Han Un Chol, a researcher at the Science Engineering Institute, has made it possible to predict the final displacement of rock mass surrounding a tunnel, which is gradually stabilized in the shape of an S-type saturated curve by using the improved nonequidistant grey Verhulst model (INGVM) with Fourier series.
The traditional non-equidistance grey model (NGM(1,1)) and non-equidistance grey Verhulst model (NGVM) were compared to examine the feasibility of INGVM application. He only used the monitored displacements during excavation to predict the final displacement and stable time of the tunnel excabated in time-dependent rock mass.
The results showed that the proposed model was highly accurate and adaptable.
The details of this are carried in his paper “Prediction of Final Displacement of Tunnels in Time-Dependent Rock Mass Based on the Nonequidistant Grey Verhulst Model” published in the SCI Journal “Mathematical Problems in Engineering”.
© 2021 KumChaek University of Technology