Ductility factor

Moore, D.R., Hooley, C.J. and Whale, M. Ductility factors for thermoplastics. Plastics and Rubber Proc. and Appl. 1(1981) p 121-127. 

The results indicate that the system containing ETPI has higher compressive yield stress and greater stiffness resulting in greater toughness as shown by the ductility factor. It was concluded that... 

The seismic engineering texts (e.g. CasteUani el al., 2000) and the many electronic computer programs now available (SAP, MARC, ADYNA, ANSYS, etc.) are a reliable basis for these analyses, but considerable computer-power may be needed, with associated high costs, where a plastic analysis of complex structures has to be performed. Similarly, the inclusion of ductility factors, where allowed and made in a conservative way, has to be done with care and attention in particular it is necessary to distinguish between ductility of a structure point (section) and the complex of the structure, to avoid an excessively conservative outcome and to highlight the possible onset of self-amplification of the cycle load-deformation phenomena P- effects), already mentioned above. 

The ductility factors calculated for the two systems with normalized strength fy = 0.25 are independent of the factor by which the ground motion is scaled. 

For items in seismic categories 1 and 3, methods relying on ductility factors applied either to internal forces, evaluated linearly, or to the input spectra should be used for checking purposes only. For items in seismic categories 2 and 4, simplified procedures using ductility factors can be followed where appropriate, but an adequate justification of their values should be provided, carried out either by testing or by analysis. 

Lee EH, Han SW (1999) Determination of ductility factor considering different hysteretic models. Earthq Eng Struct Dyn 28(9) 957-977... 

Design spectra based on specific values of the ductility factor p are introduced in the New Zealand seismic code (1992) with certain restrictions that mle out the possibility the ductility demand to exceed the provided capacity. 

Seismic actions Behavior factor (ductility factor) Reduction of seismic loads based on post-elastic behavior - depending on the material of the structiual system 5... 

The inelastic energy absorption factor (ductility factor), F, accounts for the fact that an earthquake represents a limited energy source, and many structures or equipment items are capable of absorbing substantial amounts of energy beyond yield without loss of function. 

The ductility factor fi for the ultimate limit state is calculated in accordance with the appropriate material standard, where such data are provided. Contrary to NZS 1170.5 2004, where reference is made to material standards only and a special study is required otherwise, maximum ductility factors for typical structural systems are provided directly in AS 1170.4 2007 (Table 5). Alternatively, for a specific structure, /x and Sp can be determined via a nonlinear static pushover analysis. Note also that AS 1170.4 2007 applies only to structures with ductility factor jU < 3, and when a higher ductility factor is considered, the design must be performed in compliance with NZS 1170.5 2004 provisions (Table 5). 

While NZS 1170.5 2004 does not refer explicitly to ductility factor values for the ultimate limit state, for serviceability limit state analyses of... 

Structural Design Codes of Australia and New Zealand Seismic Actions, Table 5 Ductility factor n and structural performance factor Sp for different structural systems and specific structure types (After AS 1170.4 2007)... 

Thus, the ductility factor (K,c/Sy) is a measure of the degree of crack blunting. 

Table 5.8 gives some fracture-toughness parameters and ductility factors for a number of materials. Figure 5.14 shows the variation of fracture toughness value K c for finite-width plates. Shigley and Mischke " and Sih give values for other modes of fracture. 

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