Issue 54

O. Shallan et al., Frattura ed Integrità Strutturale, 54 (2020) 104-115; DOI: 10.3221/IGF-ESIS.54.07

b) SPW-HT

a) SPW-HL

d) SPW-DU

c) SPW-HU

f) SPW-CU

e) SPW-VU

Figure 2: Geometric properties of SPSW

Modal Analysis and Initial Defect The out-of-plane initial imperfection, which may occur due to the manufacturing process, storage, and installation process should be taken into consideration in cyclic analysis, thus it might affect the plate strength. Initial imperfection was set as 1/1000 of the plate height. The eigenvalue buckling analysis was used to evaluate the imperfection distribution over the panel by multiplying the major buckling modes by the scale factor. Boundary Conditions and History Loading The nonlinear cyclic analysis was conducted on groups of thin PW and SPWs. The lateral displacement was applied to the exterior column flange. The lateral displacement increased gradually to produce drift ratios of 0.25%, 0.5%, 1%, 1.5%, 2%, 2.5%, 3% and 4%. The amplitudes were repeated twice, as shown in Fig. 1.b. The column base regions had a fixed boundary condition, in which all these nodes restrained in all the six degrees of freedom. The out-of-plane displacement for the nodes of the beam centerline and all nodes of the column-beam connections were constrained, to prevent the out-of-plane buckling of the whole system.

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