Generic sectional models - eesd-epfl/OpenSees GitHub Wiki
The user can also adapt freely the section and shear interface models to apply to the macroelement specifying them before its declaration. The sectional model represents the moment-curvature response. The shear model accounts for the shear deformations of the whole panel and is defined in terms of force-lumped displacement. The input string that follows the flag “-custom” has the format:
-custom $secI $secE $secJ $shearIP $shearOOP $h $E
Where:
| secI | tag of the section model for the base interface |
| secE | tag of the section model for the element interface |
| secJ | tag of the section model for the end interface |
| shearIP | tag of the shear model for in-plane response (nDMaterial) |
| shearOOP | tag of the shear model for out-of-plane response (nDMaterial) |
| h | height of the macroelement (dimension in the axis direction, x) |
| E | Young’s modulus of masonry |
The shear models to be defined are nDMaterial models. The first direction is the axial response, and can be equipped with any penalty stiffness (suggested: axial stiffness of the element). The second direction is the shear response, that should be equipped with the element shear stiffness. Other directions than the first two are not considered.
It is important to note that the element postulates a zero-dilatancy when imposing the equilibrium between the sectional response and the shear spring at mid-height. The material model, therefore, must respect this hypothesis, otherwise the equilibrium condition would not be enforced.
back to macroelement definition / to flags definition / home