Analysis of dynamic response of shield tunnel to explosion seismic wave

The existence of various types of joints, one of the typical characteristics of prefabricated lining structures, makes the mechanical performance of shield tunnel linings quite different from that of monolithic linings. A simplified calculation method for the dynamic elastoplastic analysis of segment lining subjected to explosion seismic wave is proposed. The lining is composed of a number of rigid arch segments that are interconnected by elastoplastic hinges. The stiffness contribution of joints and the dynamic interaction between the structure and the soil can be properly simulated with the method. As an example, the calculation of the shield section of Nanjing metro subjected to explosion seismic wave is discussed. Meanwhile, the influences of incident wave angle, rock grade and the depth of the segments on dynamic response of tunnel lining are taken into account. The result indicates that the angle of the incident waves plays an important role on the tunnel lining, where the dynamic response to obliquely incident and explosion seismic wave is larger than that to vertically incident and explosion seismic wave. The higher the surrounding rock grades, the better the capacity to resist deformation of liner structure and the better the blast- resistant characteristics of the tunnel will be. The increase of the depth of the segments would lead to notable increase of the internal force, the blast resistant characteristics could be improved by properly setting the depth of the segments.