Losing Displacement Control

The DisplacementControl static integrator is commonly employed in nonlinear static pushover analysis. Unlike LoadControl, a displacement-controlled analysis is able to get past limit points of the model response. Displacement control requires a reference load pattern, a linear time series, and a nodal DOF to control during the analysis. This post will address ways to win … Continue reading Losing Displacement Control →

Arc Length Parameters

Beyond load control, which cannot get past peaks in load-displacement response, OpenSees has several "continuation" methods for nonlinear static analysis of structural models. Implementation of continuation methods is based on the incremental-iterative framework by Clarke and Hancock (1990) with displacement control, minimum unbalanced displacement norm (MUDN), and arc length among the most frequently used in … Continue reading Arc Length Parameters →