Assessment Of Current Non-linear Analysis Models Used In Earthquake Engineering

The study aims to evaluate existing numerical nonlinear modeling techniques used in thernseismic analysis to provide a common ground for applications of the models in earthquakernengineering. Comparative analysis carried out to further asses the existing nonlinearrnnumerical finite element modeling techniques for beam-column elements subjected tornlateral loading. First, experimentally tested RC bridge column specimens downloadedrnfrom peer structural performance database and modeled in OpenSees finite elementrnsoftware. rnThe study shows, for sections exhibiting strain hardening behavior, the distributed forcebasedrnfiberrnmodelsrnprovidernarnmorernaccuraternresponse.rnThernresponserncomputedrnusingrnthernrndistributedrnrndisplacement-based fiber models overestimate the capacity of the members.rnTherefore, to accurately describe the inelastic response, several displacement-basedrnelements are required. rnFor the section exhibiting strain-softening behavior, the localization issue affected bothrnthe displacement-based and force-based formulations. Therefore, material regularizationrnis required to overcome mesh dependent response. Furthermore, for section showingrnsoftening behavior, the regularization of both concrete and steel materials is required. Thernconcentrated force-based plastic hinge model adequately captures the nonlinear response.rnThe lumped plasticity with zero-length hinge model captures the initial stiffnessrnadequately, but, inadequate to capture the cracking and onset of overall yielding.rnFurthermore, the model underestimates the ultimate capacity in terms of base shear. rnFinally, to evaluate the numerical accuracy of the models, two-story and three-story RCrnframes modeled in OpenSees finite element software. For nonlinear analysis of the RCrnframes, the distributed force-based fiber models capture the inelastic response accurately.rnIncreasing the axial load on the two-story RC frame exhibits mesh dependent results. Forrnthe frame under strain-softening behavior, the material regularization techniquesrnsuccessfully tackle the localization issue.

Get Full Work

Report copyright infringement or plagiarism