Section Library

For the case of the uniaxial section, moment-curvature and axial force-deformation curves are defined independently, and numerically.

For the case of the fiber sections (steel and RC), uniaxial materials are defined numerically (stress-strain relationship) and are combined into a fiber section where moment-curvature and axial force-deformation characteristics and their interaction are calculated computationally.

Moment-Curvature Analysis

• This example introduces the moment-curvature procedures for sections in 2D or 3D space, as built in the previous section. (the only difference between them is the degree-of-freedom corresponding to curvature).
• The moment-curvature analysis of a section is by creating a zero-length rotational-spring element. This section is subjected to a user-defined constant axial load and to a linearly-increasing moment to a user-defined maximum curvature.

Run

The model and analysis combinations for this example are numerous. The following are an small subset, for demonstration purposes:

• To run Uniaxial-Section Model, 2D

puts " --------------------------------- 2D Model ---------------"
puts " a. Uniaxial Section"
source Ex9a.build.UniaxialSection2D.tcl
source Ex9.analyze.MomentCurvature2D.tcl

• To run RC Section: Rectangular, Confined, Symmetric Model, 3D

puts " --------------------------------- 3D Model ---------------"
puts " d. RC Section: Rectangular, Confined, Symmetric"
source Ex9d.build.RectConfinedSymm3D.tcl
source Ex9.analyze.MomentCurvature3D.tcl