Long period structures

A special case of long-period structure to be considered is the oI40-AuCu(II) type structure which has ID substitutional and displacive modulations (Fig. 3.41). We must first mention that ordering of the Au-Cu face-centred cubic (cF4-Cu type) solid solution, having a 50-50 atomic composition, re-distributes Cu and Au atoms... 

Selke, W. (1989) Long period structures in alloys-statistical mechanics in the ANNNI model and related concepts. In Alloy Phase Stability, eds. Stocks, G.M. and Gonis, A., NATO ASI Series, Series E Applied Sciences (Kluwer Academic Publishers, Boston, USA), Vol. 163, p. 205. 

Long-Period Interfaee Modulated Struetures. Many long-period structures are derived from simpler. structures by the periodic introduction of planar translation interfaces. Typical examples are the long-period antiphase boundary structures in many ordering alloy systems such as Au-Mn. Cu-Au, and the shear structures derived from a simple transition-metal oxide structure such as W03 j, Ti02-v Such compounds produce charac-... 

If the displacement vector R is parallel to the interfaces, the latter are termed conservative since the long-period structure has the same chemical composition as the basic structure. 

Some Observations and Proposed Improvements of the Procedure, Included in FEMA-356 It was observed that the characteristic periods which are used to differentiate the response of short- versus medium- and long-period structures were found to be shorter than those observed from nonlinear response history analyses. This can result in an underestimation of the inelastic deformations for the periods between the characteristic period and the periods that are approximately 1.5 times the characteristic period. 

Some Observations and Proposed Improvements in the Procedure Included, in ATC-40 The accuracy of the estimated maximum displacement response in long-period structures depends on the hysteretic behavior type. 

Drift Earthquake records Long-distance effects Long-period structure Tohoku earthquake... 

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