simdesign.rcmrf.bnsm.baselib

BNSM Base Library

This package provides the abstract modelling interfaces of the Building Nonlinear Structural Model (BNSM). It defines the component-level architecture and modelling contracts used by nonlinear model implementations (e.g., DP01, CP01).

While higher-level BNSM packages provide instantiable component implementations, baselib establishes the abstract definitions of these components that bridge the BDIM design layer and the OpenSees analysis domain.

This package is intentionally abstraction-focused to allow flexible extension, alternative modelling strategies, and future nonlinear formulations.

Modelling Strategy

The modelling philosophy is component-based and macro-model oriented, suitable for nonlinear seismic analysis of reinforced concrete (RC) frame buildings.

The base components defined here include:

  • Beam and Column: Abstract beam-column interfaces supporting plastic-hinge material formulations and section aggregation strategies.

  • Joints: Abstract joint representations supporting rigid, elastic, or inelastic rotational spring modelling.

  • Infill: Abstract equivalent diagonal strut interface for masonry panels.

  • Floor Diaphragm: Interface for rigid diaphragm constraints.

  • Foundation: Base support node representation (extendable for SSI).

  • Node: Structural node abstraction with optional translational masses.