The Effect of Incremental Loading on Creep Behavior of Metals
In structural analysis it is of basic importance to know whether small deviations (in stress and strain) from a basic state obey a linear visco-elastic law for a given metallic material. The paper starts with a discussion of a proposed series of tests by which the existence and the form of such linear relations may be determined. In the following section preliminary results of the proposed type of tests with lead wires are dis cussed. Finally the importance of the rational determination of time operators in the visco-elastic law is illustrated in the case of creep buckling of initially straight columns. The buckling criteria of RABOTNOV SHESTEBIKOV and SHANLEY are critically examined. The importance of the critical load based on the inelastic modulus is stressed.
KeywordsCritical Load Creep Strain Creep Behavior Incremental Strain Strain Response
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