...
| Info |
|---|
This page is devoted to frequently asked questions (FAQ) related to hinges. |
On this page:
| Table of Contents |
|---|
Default hinge properties are derived from which source?
...
Overwrite options are available for the manual definition of hinge behavior or certain hinge properties.
| Show if | ||
|---|---|---|
| ||
Related Incidents:
|
How is yield rotation calculated?
...
For the automatic FEMA frame hinges, the yield rotation is specified in the code (ASCE 41-06, Table 5-6) as the chord rotation of the full member length due to plastic moment at one end. Specifically, the yield rotation is Mp/(6*E*I/L), where Mp = Z*fy, and L is the frame object (not element) length and this is how the yield rotation is determined in the program.
| Show if | ||
|---|---|---|
| ||
Related Incidents:
|
Why do hinge results deviate from the defined hinge backbone?
...
Answer: Frame hinges must be specified to model nonlinear frame behavior. Nonlinear material parameters are then associated with hinge response, including the interaction surface and the moment-rotation curves which describe post-yield behavior. When implementing fiber hinges, material definition controls the stress-strain relationships of individual fibers.
| Show if | ||
|---|---|---|
| ||
VERIFY |
What is the difference between hinge and hysteretic-link application?
...
Answer: Yes, energy is dissipated for PM and PMM hinges. In fact, these always use isotropic dissipation, which dissipates more energy than the kinematic, Takeda, and Pivot rules available for the single DOF hinges.
| Show if | ||
|---|---|---|
| ||
Related Incidents:
|
How does the plastic-hinge deformation-curve scale factor affect analysis?
...
Answer: To assign hinges to a steel pipe section, define a User Hinge, then assign this hinge type to the section. As an alternative, fiber hinges may be assigned. The software will then automatically determine the fiber layout according to the section shape.
| Show if | ||
|---|---|---|
| ||
Related Incidents:
|
Is there an explanation for Rp and the coupled P-M-M hinge equation Rp = Rp2 cos Φ + Rp3 sin Φ?
...
For reinforcement in concrete members, minimum strengths are currently being used for both deformation-controlled and force-controlled hinges.
| Show if | ||
|---|---|---|
| ||
Related Incidents:
Related emails:
|
Does unbraced length influence the FEMA P-M hinge interaction surface?
...
Users who wish to consider unbraced length during interaction-surface calculation have the option to manually define P-M hinge properties and yield criteria. Moment-rotation curves may be developed through nonlinear analysis of members modeled using shell elements which would capture localized buckling of slender members.
| Show if | ||
|---|---|---|
| ||
Related Incidents:
|
Why are plastic-hinge colors not displayed when viewing FNA deformation?
...