Analytical and Field Evidence of the Damaging Effect of Vertical Earthquake Ground Motion

The paper is an attempt to collate field evidence and results from dynamic analysis on possible structural effects of strong vertical ground motion. Observational evidence from three earthquakes are presented and assessed with regard to failure modes of buildings and bridges attributable to high vertical earthquake forces. Analytical results from previous studies for the same structural types are reviewed. These collectively confirm that structural failure may ensue due to direct tension or compression as well as due to the effect of vertical motion on shear and flexural response.