Journal of Earthquake and Tsunami

A rigorous mathematical formulation for the kinematic response of single piles embedded in multilayered soil subjected to vertically incident P-waves is proposed based on the modified Vlasov model. The governing equations and boundary conditions of the soil–pile system are obtained by using Hamilton's principle. The soil–pile interaction and the physical properties of the layered soils are taken into consideration in the proposed model. The accuracy of the proposed method is validated by the comparison of the proposed solution results with some existing solutions. A parametric study is conducted to investigate the effects of the soil inhomogeneity on the kinematic response of single piles. The results reveal that: as for the two-layered case, the thickness of the upper soft layer has a significant influence on the kinematic response of single piles; as for the three-layered case, the soil–pile interaction is very sensitive to the thickness and Young's modulus of the middle layer.

In recent years, the apparent seismic activity around Longmen Shan and its front has included the Wenchuan (Ms8.0) Earthquake and the Lushan (Ms7.0) Earthquake, occurring in 2008 and 2013, respectively. Based on the focal mechanism solution, rupture processes, seismic intensity, surface deformation, and aftershocks of the Lushan Earthquake and the active fault on Longmen Shan, we divided the Longmen Shan and its front into two tectonic deformation belts, the Longmen Shan thrust belt and the frontal propagation belt. By comparing the differences in the tectonic deformation styles, active faults, and earthquake histories of the two belts, we propose two kinds of seismotectonic models: one is a thrusting belt characterized by napping and detachment, and the other is a frontal propagation belt characterized by thrusting and detachment folding. By analyzing the seismogenic mechanisms of thrusting and detachment folding in the frontal propagation belt during the Lushan Earthquake, we have inferred that the Lushan Earthquake was formed by thrusting and detachment folding in the frontal propagation belt. The seismogenic fault of the Lushan Earthquake was the Dayi Fault, which dips NW with a listric surface, and converges on the detachment surface. The detachment surface is the seismic source layer of the Lushan Earthquake.

Hundreds of bridges were washed away or heavily damaged by tsunami waves during the two tragic tsunamis that devastated the west coast of Sumatra Island, Indonesia, in 2004 and North East Japan in 2011. This vast damage was a clear warning for scientists to pay more attention and investigate, assess and mitigate the effect of tsunami loads on various structures including bridges. This multidisciplinary research presents a review of the literature and comprehensive evaluation on previous research concerning the effect of tsunamis on bridges. It begins with the basic evaluation of tsunami loads on bridges through to the current tsunamis. The experimental, numerical and survey reports on tsunami loads on bridges are reviewed and discussed. Tsunami mitigation systems on bridges are examined and classified in this paper. In addition, the open issues and challenges are outlined for future studies to help evaluate new research concerning the assessment, design and mitigation of tsunami loads on bridges.