FAILURE MECHANISM OF SINGLE-LAYER LATTICED CYLINDRICAL SHELLSSUBJECTED TO SEVERE EARTHQUAKE LOADINGS

摘要

Nowadays anti-seismic behaviors of space frames due to severe earthquakes is not yet well-knownrnalthough occurrences of earthquakes have caused many deaths and injuries. In this paper, plastic developmentrnprocess and failure characteristic of single-layer latticed cylindrical shells are studied by investigating curves ofrnseveral characteristic response targets verifying with the increase of earthquakes, which are calculated byrnnon-linear time-history analysis due to 3-dimension earthquakes. Failure mechanism of such structures isrndiscussed. Furthermore, elasto-plastic earthquake response regularities and failure characteristic for shells withrndifferent geometry parameters are summarized herein. The study reveals that although the failure of space framesrnresearched in the paper is shown as a sudden increase of displacement response, there must be a certain plasticrndevelopment process before the failure appears. In fact, the failure of space frames is caused by the incessantrninteractive actions of the plastic development and deformation. And shells with higher rise-span ratios present apparent tendency to dynamic unstability.