Local buckling defined

The terms buckling and collapse are often used interchangeably. Buckling is defined as localized failure caused by overstress or instability of the wall under compressive loading. Collapse is a general failure of the entire cross section by flattening due to external pressure. 

The local control strengths of the control rods Included in the table are defined as the change in buckling of a region with a cross sectional area of II90 In. (32 in. x 36 ln.) The migration areas listed gre those used to derive. the reactivity effect by the relationship k/k The full-... 

Figure 5.150. An equatorial dark field image of PBO fiber heat treated at 600°C (A) shows well defined and localized boundaries between the kink and the deformed fiber. A low dose HREM 0.55 nm (200) micrograph (B) of a kink in PBO heat treated at 665°C shows (200) lattice fringes of spacing 0.55 nm. The kink band clearly contains very localized high angle bending or buckling of the stiff polymer chains. (From Martin and Thomas [706] used with permission.)...

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