Local buckling

This equation gives the critical pressure required to cause general buckling local buckling can occur at a lower pressure. Karman and Tsien (1939) have shown that the pressure to cause a dimple to form is about one-quarter of that given by equation 13.59, and is given by ... 

Both FEA and experimental impacts were used with high-speed photography to show that the shells could buckle locally under a stud impact. The best guards use complex shaped shells to increase the transverse bending stiffness. 

Point defects. Point defects (Fig. 5.1) are limited to a single point in the lattice, although the lattice will buckle locally so that the influence of point defects may spread quite far. A Frenkel defect consists of a misplaced interstitial atom and a lattice vacancy (the site the atom should have occupied). For example, silver bromide, which has the NaCl structure, has substantial numbers of Ag+ ions in tetrahedral holes in the ccp Br array, instead of in the expected octahedral holes. Frenkel defects are especially common in salts containing large, polarizable anions like bromide or iodide. 

The stiffness of the face and core elements of a sandwich RP must be sufficient to preclude local buckling of the faces. Lx)cal crippling occurs when the two faces buckle in the same mode (anti-symmetric). Local wrinkling occurs when either or both faces buckle locally and independently of each other. Local buckling can occur under either axial compression or bending compression. Resistance to local buckling is... 

For the "nonaromatic members, an X-ray structural determination of the carboxamide 1 (R = CONMe2) shows the heavily buckled geometry of a re-localized system.10... 

The design is supported by stress, fatigue, buckling and safety analysis, and relies on standard steel. Only in localized areas would higher quality (albeit still standard) steel be needed. Carbon hber instead of steel pre-tensioning cables may provide higher performance at a marginal cost increase, but are not strictly required. 

Buckled surface models for the two other copper sulfur phases were proposed that rationalised the STM, LEED and SEXAFS data (Figure 10.5). Note that the local adsorption site of the sulfur adatoms in both the p(3 x 2) and p(5 x 2) structures is the four-fold hollow in agreement with the SEXAFS18 measurements but looking at the structure from above with the STM, the periodicity of the structure suggests a variety of different adsorption sites. 

A comprehensive list of behavioral phenomena and physical attributes affecting the strength and stability of steel frames is compiled in White 1991. Some of the items listed include initial imperfections, residual stresses, initial strains, construction sequence, effects of simultaneous axial force, shear and moment on section capacities, P-dclta effect, local buckling and spread of inelastic zones in members. A similar list of items could be compiled for reinforced concrete and other structural materials. It is clear that a comprehensive advanced analysts can become quite... 

Heteronins 24-27 have been the subject of extensive spectroscopic and chemical studies, and it has been established that certain members, such as oxonin (24a) and those azonines incorporating electron-withdrawing N-substituents (24b and 25) possess heavily localized polyenic frames, whereas others, such as parent azonine (26a) and its anion (26b-f), are extensively delocalized and decidedly aromatic.30 A third subgroup consisting of the TV-alkyl azonines (27) was said to be nondescript . In specific terms, the polyenic members of the family were shown to be (i) atropic by 4H NMR, (ii) -localized and heavily buckled by UV,30 13C NMR,34 and an X-ray determination on urea 25c,35 (iii) thermally labile, readily isomerizing to the c -bicyclo[4.3.0]triene frame... 

---