Issue 30

D. Tumino et alii, Frattura ed Integrità Strutturale, 30 (2014) 317-326; DOI: 10.3221/IGF-ESIS.30.39

0.0021

0.0024

x-type beam

y-type beam

0.002

0.0022

0.0019

0.0018

0.002

0.0017

0.0018

y = 3.61E-09x + 2.97E-04

0.0016

y = 4.70E-09x + 2.51E-04

0.0015 w/PL [mm/N]

0.0016 w/PL [mm/N]

0.0014

0.0014

0.0013

0.0012

0.0012

200000

250000

300000

350000

400000

300000 350000 400000 450000 500000 550000

L 2 [mm 2 ]

L 2 [mm 2 ]

Figure 5 : Experimental results of the variable span TPB tests on x- and y-type sandwich beams.

Figure 6 : Experimental setup for the TPB tests.

x-type beam

D

[N/mm]

x D [Nmm]

Span [mm]

620

570

520

470

Qx

' x D [Nmm] 3.9E6 3.8E6 3.7E5 3.57E3 4.43E6

9.96E2

y-type beam

y D [Nmm]

Qy D [N/mm]

Span [mm]

721

671

621

571

'

y D [Nmm] 5E6 4.9E6 4.7E5 4.66E3 5.76E6 8.42E2 Table 3 : Results of TPB tests on x- and y-type sandwich beams: apparent and corrected values of stiffness.

Application to coupled mode cases In the cases studied so far, only uncoupled load configurations were analysed. Aim of this work is to give a versatile numerical tool able to simulate a complex case where coupling between flexural deformation in x and y direction and torsional deformation can occur. For this reason two cases have been simulated for which no closed form solution exist. Both loading schemes depicted in Fig. 8 are characterized by the presence of multiple terms in the matrix D.

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