Super‐detailed FEM simulations for full‐scale steel structure with fatal rupture at joints between members—Shaking‐table test of full‐scale steel frame structure to estimate influence of cumulative damage by multiple strong motion: Part 1

Abstract

There have been several studies on analyses using finely meshed finite‐element (FE) models to understand in detail the behaviors of buildings during severe earthquakes. The accuracy of such analyses is often validated by comparing the results to the corresponding full‐scale shaking‐table test. While this approach is highly successful in terms of accuracy, no studies have considered the effect of fractures of members. In this study, numerical analyses are conducted for a steel structure subjected to multiple series of excitations in a full‐scale shaking‐table test considering fractures. The structure is modeled with planar and solid finite elements, and the fracture is treated by the mandatory deletion of elements at the time at which the fracture is observed in the experiment. The results show that by considering the fracture of steel members with the deletion of elements, the history of input excitations, and the resulting damages, the behaviors can be simulated analytically with a much higher accuracy.

Detailed Fem Analysis for Full Scale Steel Structure Considering Fracture of Beam Ends

“…Contact condition was considered for adopting to parts that was actually in contact between separated members. The further modeling details are described in previous studies [3], [4]. It is confirmed that natural periods obtained by eigenvalue analysis using this model agree with observed result of the actual specimen in the previous study [3].…”

“…Miyamura et al report that nonlinear behavior of shaking table test of a 4-story steel building can be replicated by using a fine meshed FE model with solid elements [1]. The authors also report about FE analysis examining a full-scale shaking table test of a 3-story steel structure that is the analytical target of this paper modeling mainly shell elements [2], [3]. These reports conclude that FE models that are finely meshed to reproduce the entire shape of structures as precisely as possible can appropriately replicate non-linear behaviors of building structures under earthquake excitations.…”

“…In the referenced report [1], the analytical target was the case wherein a collapse of the structure was observed because of not fracture but local buckling of the firststory columns. In the authors' previous report [3], fracture of members is not predicted but a pseudo fractures are demonstrated by eliminating elements in areas wherein the fracture occurred actually in the experimental test.…”

“…Above-referenced three reports [1], [2], [3] do not simulate fracture of members in their analytical procedures. In the referenced report [1], the analytical target was the case wherein a collapse of the structure was observed because of not fracture but local buckling of the firststory columns.…”

“…The analytical target is a full-scale shaking table test of a 3-story steel structure as in the previous study [3]. The accuracy of the prediction for fracture-occurring timing at the steel members and validity of responses obtained by numerical simulation are investigated.…”