Issue 74

A. M. Almastri et alii, Fracture and Structural Integrity, 74 (2025) 342-357; DOI: 10.3221/IGF-ESIS.74.21

Figure 2: Convergence of finite element modeling of WS-12-N specimen.

(a) (b) Figure 3: (a) loading and boundary conditions of WS-12-N specimen, and (b) first buckling mode of WS-12-N specimen. Buckling moments simulation results are illustrated in Fig. 4, along with the experimental values, and values calculated by AISC-360 specifications [25] and Eurocode 3 [26]. The web buckling strength ௡ calculated by AISC-360 (which calls it web crippling) is obtained by the equation (in British units): 1.5 2 0.80 1 3 yw f b w n w f w EF t l t R t d t t                         (1) where w t is web thickness, f t is flange thickness, d is the full depth of the member, b l is the length of bearing, E is the modulus of elasticity, and yw F is the specified minimum yield stress of the web. As the load in the experiment was applied to the tension flange, the length of the bearing is assumed to be zero here. It should be noted that by setting the bearing length to zero, the value obtained by Eqn. (1) becomes independent of web height. So, the calculated web buckling load will be the same for the two samples. However, the buckling moment will differ for the two specimens due to the difference in span and loading position. For the Eurocode 3, design resistance to local buckling under transverse force should be calculated from:

F L t

yw eff w



F

(2)

Rd



M

1

where 1 M  is a safety factor, taken as 1 here. A good agreement is noticed between experimental and numerical buckling moments for the girders. As shown in Fig. 4, the eff L is the effective length for resistance to transverse forces, and

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