MUST-SIM Facility

NEESR-SG: Seismic Simulation and Design of Bridge Columns under Combined Actions and Implications on System Response

Project Overview

The performance assessment of bridge piers subjected to the complex loading combination of bending, shear, axial load and torsion has been a challenge to structural engineers. Analytical solutions that were developed for such combined loadings are not sufficient and the lack of large scale experiments has deprived the community from the necessary resources to improve the models. To provide a context for this complex problem and to overcome limited laboratory capabilities, the pseudo dynamic (PSD) test method will be employed using the Multi-Axial Full-Scale Sub-Structured Testing and Simulation (MUST-SIM) facility. In addition, UI-SIMCOR, the NEES@UIUC simulation coordinator, will be utilized throughout the study. UI-SIMCOR is a robust tool for combining any number of experimental and analytical sites within an integrated simulation of a complex structure, its foundations and soil-structure interaction. The research program focuses on determining the impact of varying vertical motions on the shear-flexural-axial interaction behavior of bridge columns under combined loading.
Analysis and Design: A series of bridge structures subject to different levels of earthquake excitations will be analyzed using existing finite element software packages (e.g. OpenSees and Zeus-NL, the MAE Center advanced analysis platform) as well as UI-SIMCOR. The bridges analyzed in the study will be selected to represent conditions resulting in high levels of simultaneous transverse and vertical accelerations on the columns. The goal of the analytical study is to investigate the seismic response of these bridge systems, including foundations and surrounding soils, so that the appropriate multidirectional loading and boundary conditions for columns can be obtained.
Experimental simulation (PSD Test): Based upon the results of the analytical investigation, PSD tests of large-scale and small-scale bridge columns will be tested with different aspect ratios and seismic design details using the MUST-SIM facilities. In order to realistically represent the loading experienced by bridge columns in earthquakes, selected bridge systems from the previous analysis will be used during full hybrid simulations.
It is anticipated that important effects such as the influence of axial force variation on the shear deformation and failure of bridge columns due to combined loading (i.e. transverse and vertical ground motion) can be characterized. The objectives will be achieved by deploying the approaches of combining tests and analysis, and by optimal use of advanced test control and analysis. Due to the comprehensive nature of the project results, several outcomes will result. The results can be used to propose appropriate design and assessment approaches for codes as well as provide the designer with appropriate means for determination of limit states and structural response.
This material is based upon work supported by the National Science Foundation under Grant No. 0530737. 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.

Project Staff

Faculty Investigators

Principal Investigator: University of Nevada, Reno

David Sanders, Professor, Dept. of Civil and Environmental Engineering, University of Nevada, Reno, Reno, NV 89557, (775)-784-4288, sanders@unr.edu

Co- Principal Investigator: University of Illinois, Urbana-Champaign

Amr Elnashai, Bill and Elaine Hall Endowed Professor of Civil Engineering, Director of Mid-America Earthquake Center, Dept. of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61820, (217) 265-5497, Email: aelnash@uiuc.edu

Co- Principal Investigator: University of Missouri, Rolla

Abdeldjelil “DJ” Belarbi, Distinguished Professor, Dept. of Civil, Architectural and Environmental Engineering, University of Missouri-Rolla, 323 Butler-Carlton Hall, Rolla, MO 65409, (573) 341-4478, belarbi@umr.edu

Pedro Silva, Associate Professor, Dept. of Civil and Environmental Engineering, The George Washington University, Phillips Hall, 642 Academic Center, Washington, DC 20052, silvap@gwu.edu

Ashraf Ayoub, Associate Professor, Dept. of Civil, Architectural and Environmental Engineering, University of Missouri-Rolla, 324 Butler-Carlton Hall, Rolla, MO 65409, (573) 341-7604, ayoub@umr.edu

Co- Principal Investigator: University of California, Los Angeles

Jian Zhang, Assistant Professor, Dept. of Civil and Environmental Engineering, University of California-Los Angeles, CA 90095, (310) 825-7986, zhangj@ucla.edu

Co- Principal Investigator: Washington University, St. Louis

Shirley Dyke, The Edward C. Dicke Professor of Engineering, Dept. of Civil Engineering, Washington University, St. Louis, MO 63130 (314) 935-5695, sdyke@wustl.edu

Post-Doctoral Assocaites, Graduate Students, and Undergraduate Students

Sung Jig Kim, Graduate Research Assistant, UIUC, sjkim4@uiuc.edu

Cutis Holub, Graduate Research Assistant, UIUC, cholub@uiuc.edu

Poject Schedule

Project Initiation: September 15, 2005

Experimental Testing at MUST-SIM: 2007

Project Termination: August 31, 2009