professor ben schafer's thin-walled structures research group - johns hopkins university


Material on this page is based upon work supported by the National Science Foundation (NSF) under Grant Number 1235196 (duration 2012-2015) and is a collaborative project with NSF Grant Number 1235238, PI'ed by Prof. Mazdak Tootkaboni.


Collaborative Research: Uncertainty Quantification and Model Validation in Thin-Walled Structures: A Probabilistic Paradigm for Advancing Analysis-Based Design 


A collaboration with Professor Mazdak Tootkaboni at UMass-Dartmouth


Condensed Abstract

This project will pursue research towards an advanced framework for nonlinear stability analysis of thin-walled structures taking into account the uncertainty associated with geometric imperfections. Thin-walled structures most commonly fail in buckling failure mode. Whether this buckling is benign or catastrophic depends, to a great extent, on the details of the structure, most importantly its geometric imperfections. The research aims at providing a leap towards uncertainty quantification and model validation in the analysis of thin-walled structures by devising a probabilistic paradigm that uses advanced uncertainty quantification techniques along with novel structural analysis methods. Methodologies for the characterization and representation of geometric uncertainties as well as probabilistic imperfection sensitivity analysis frameworks are proposed that have the potential to pave the way for a fully stochastic nonlinear analysis of thin-walled structures. The proposed techniques are complemented by experimental measurements of imperfections with high accuracy, and testing of imperfect members. If successful, the results of this research will transform how geometric imperfections are handled in advanced analysis-based design of thin-walled structures. Because of the very general and mathematics-driven nature of the stochastic approaches adopted in this project, the methodologies developed will be applicable to a wide variety of problems and will have potential impact across all science and engineering disciplines.In addition to academic dissemination through conferences and papers and providing all developed work as open source, the PIs will capitalize on their involvement in engineering committees (e.g. AISC, AISI etc.) to disseminate the findings outside of the academic community.



Asst. Prof. Mazdak Tootkaboni, UMass-Dartmouth, PI

TBD, UMass-Darthmouth, Graduate Research Asst.

Prof. Ben Schafer, Johns Hopkins, PI

Ms. Xi Zhao, Johns Hopkins, Graduate Research Asst.

Brooks Gearhart, Johns Hopkins, High School (Baltimore Polytechnic) Research Asst.


Work Products to date

Presentation regarding new imperfection measurement rig to American Iron and Steel Institute Committee on Specifications and Committee on Framings Standards. (February 2013) (July 2013)


Zhao, X., Schafer, B.W. (2013). "Non-contact Full-Field Measurement of Geometric Imperfections in Cold-formed Steel Member." Presentation at ASCE Engineering Mechanics Institute. August 4-7, 2013, Northwestern University, Evanston, IL. (presentation) (abstract)


Working through the CFSRC and with Professor Moen's research team to develop an imperfections database for cold-formed steel members. First face-to-face meeting 13 September 2013.



Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.


Last updated 9/10/13