Abstract: Deformation joints are universal in underground utility tunnels that belong to the shallow-buried and slender structure. Under seismic loads, the vibration response of the underground structure with a joint will be affected to a great extent. However, the studies on this problem are limited. In this paper, based on the shaking table model test that considers the influence of joints, the seismic response characteristics of the underground utility tunnel under seismic excitation with different waveforms and different peak accelerations were studied. The acceleration, soil pressure, displacement, strain, and bending moment were measured and analysed. The results indicated that the vibration of the tunnel was mainly affected by the surrounding soil and the sidewall of the joint section separated from soil during earthquake excitation, while the tunnel structure displayed a good integrity. The displacement of the tunnel joint was relatively small under the strong earthquake, which did not result in large-scale deformation failure. The distribution of seismic soil pressure under the strong earthquake was nonlinear. The moment on the joint section was less than that in the middle section in the earthquake, which was beneficial to seismic performance.

Key words: utility tunnel, shaking table test, dynamic response, acceleration