A SEISMIC COLLAPSE ANALYSIS CODE FOR FRAMED STRUCTURES
USING ASI-GAUSS TECHNIQUE
D. ISOBE1, W.S. HAN2, and T. MIYAMURA3
1Assoc. Prof., Div. Engineering Mechanics and Energy, Univ. of Tsukuba, Ibaraki, Japan,
2
LG Chem Ltd., Korea,
3Lecturer, Dept. Computer Science, Nihon. Univ., Fukushima, Japan,Correspond to Prof. D. ISOBE (isobe@kz.tsukuba.ac.jp)

Keywords: Seismic Collapse Analysis, Finite Element Method, Framed Structures, ASI-Gauss Technique

0.02

0.01

0-0.01-0.02

E-Defense
E-Simulator
ASI-Gauss code
010
Time [s]20Figure 2. Comparison of the time histories of the interstory
drift angle on the 1st floor (X-direction)
1500

EW, roof

1000
Displacement [mm]2. NUMERICAL RESULTS
The performance of the seismic response analysis codeusing the ASI-Gauss technique is validated by being
compared to an experimental result obtained by a fullscale shake-table test using the E-Defense for a fourstory steel frame, as shown in Fig. 1(a). Figure 1(b)shows the detailed model constructed for the E-Simulator,
where the mesh has 5,181,880 hexahedral solid elements,
7,523,255 nodes and 22.57 million degrees of freedom(DOFs) [3], and Fig. 1(c) shows the beam element modelfor the ASI-Gauss code constructed with 1,388 elements,995 nodes and 5,970 DOFs. The 60 % JR Takatori
seismic wave recorded on the shaking table is used as theinput wave. Although the computational cost using theASI-Gauss code is very small compared to that of the ESimulator, the numerical results for the four-story steel
frame obtained by the ASI-Gauss code has no demerit tobe confirmed compared to those obtained by the detailed
analysis performed by the E-Simulator, and they also
showed good agreement with the experimental results
obtained by the E-Defense, as shown in Fig. 2.
Figure 3 shows a comparison of the deformations of
the 31-story steel building frame models obtained byboth codes at 6.21 s of the input ground motion, where alarge relative displacement at the top of the cornercolumn of the 31st story is observed. The deformations
agreed well as a whole.

(a) E-Defense(b) E-Simulator (c) ASI-Gauss
Figure 1. Four-story steel frame models
Story drift angle [rad]1. INTRODUCTIONAn adaptive finite element code using the linear
Timoshenko beam elements based upon the adaptively
shifted integration (ASI) technique and its refinedversion, the ASI-Gauss technique [1], has beendeveloped to analyze various dynamic problems offramed structures. It gives highly accurate solutions witha minimum number of elements per member, byadaptively shifting the numerical integration point in anelement to a location where that of a plastic hinge can beprecisely expressed. The finite element code using thetechnique drastically decreases memory resources andcomputational time.
In this presentation, capabilities of the numerical codein seismic response analyses are shown by comparing theresults with detailed numerical simulations performed by
the parallel finite element analysis code, the E-Simulator
and experimental results obtained by the full-scale shaketable test using the world’s largest shaking table, the EDefense [2].

5000-500-1000-1500

E-Simulator
ASI-Gauss code
05Time [s]10(a) E-Simulator (b) ASI-Gauss(c) Displacements
Figure 3. Comparison of the deformation (magnified 10times) at 6.21 s and displacements for the 31-story steelbuilding frame
3. CONCLUSIONSThe ASI-Gauss code can obtain highly accurate
seismic response solutions of building frames as well as
their collapse modes. An example of a seismic pounding
and collapse analysis is also to be shown in thepresentation.
REFERENCES[1] K.M. Lynn, D. Isobe, Int. J. Numer. Meth. Eng. 69-12(2007) 2538-2563.
[2]http://www.bosai.go.jp/hyogo/research/project_result/pdf/steel_3.pdf.
[3] T. Miyamura et al., Prog. Nucl. Sci. Tech. 2 (2011)651-656.