TUNNEL MEASUREMENT SYSTEM AND ITS APPLICATION TO KOREA HIGH SPEED RAIL TUNNELS

초록

A health monitoring system installed in the Korea High Speed Rail tunnel is briefly explained in this paper and a new system identification method based on convergence measurement data is proposed to find possible damage in the tunnel liner. For this, an inverse problem in which deformation data and dead load of concrete lining are known a priori is introduced to estimate the degree and location of the damage. Models based on uniform reduction of stiffness and smeared crack concept are both employed to compare the efficiency and relative advantages of each model. Numerical analyses are performed on the idealized tunnel structure and the effect of white noise, common in most measurement data, is also investigated to better understand the suitability of the proposed models. As a result, model 1 based on uniform stiffness reduction method is shown to be relatively insensitive to the noise, while model 2 with the smeared crack concept is proven to be easily applied to the field situation since the effect of stiffness reduction is rather small.