Seismic design of shallow tunnels
A new method for the design of shallow tunnel linings located in seismic regions is proposed. The stress state of underground objects are estimated on the base of an analytical solution of the corresponding plane problem of the theory of elasticity. Loads applied to the design scheme are determined considering the action of seismic waves reflected from the Earth surface. The value of amplitude stresses in the incident wave characterizes the intensity of the seismic action and is determined according to the value of peak ground acceleration corresponding to the level of the Earthquake investigated. The most dangerous stress state, which may appear during the Earthquake of certain intensity in every considered radial section of the lining is the result of the calculation. Examples of the design are given.