Model Test Research of the Influences of Rock-Fall Impaction on Accelerations of the Cut-and-Cover Tunnel Structure

On conditions of different weight and height, the tunnel portal structure’s accelerations evoked by rock-fall impaction have been researched in laboratory by using a 1/30 scale similar model. The study shows that the normal acceleration value is the biggest, the lateral acceleration is second and the longitudinal acceleration is the minimum. There is a simple linear relationship between the structure’s acceleration, the rock weight and the rockfall height when the slope gradient is 1:0.5 and the slope surface is slippery. The multiple linear relationship between the structure’s normal acceleration, the rock weight and the rockfall height has been obtained.