Electronic Theses and Dissertations

Date of Award


Document Type


Degree Name

M.S. in Engineering Science


Civil Engineering

First Advisor

Christopher L. Mullen

Second Advisor

Hunain Alkhateb

Third Advisor

Ahmed Al-Ostaz

Relational Format



Structural stability has been the subject of much research in recent years. Simply, structural stability may be vieas the ability of the structure’s response to be relatively unaffected by perturbations to its system. Stability of low-rise steel-moment framed buildings and their sensitivity to perturbations from significant damage are the focus of this work. Perturbations, or changes from the normal state of the structural system, have the ability to affect the structural response. Second-order geometric effects imposed through column axial loads, and/or initial out-of-plumbness during the construction process, are a comperturbation in steel framing systems. If the structural members subjected to these effects are damaged through a specific hazard, the effective stiffnesses of the members are reduced, and the consequence of the individual perturbations is amplified. Because such scenarios are feasible during the lifetime of a structure, robust methods to investigate structural stability sensitivity to damage and second-order geometric effects are desired. A stiffness reduction factor is introduced into the analytical finite element formulation of a portal frame to account for hazard-independent damage. Second-order geometric effects are included in this formulation. This finite element formulation is created using Mathematica and its formulation is verified against idealized elastic critical buckling load theory. Next, the formulation is generalized to provide an ability to analyze the elastic buckling load of a wide range of portal frames. The finite element software, MASTAN2 and SAP2000 are utilized for verification purposes. ABAQUS/CAE is chosen to further examine the stability of steel-moment frames. Several cases of gravity and lateral loads are applied to planar frame models. Again, the hazard-independent damage is introduced to the system in various cases and nonlinear geometric effects are accounted for. Results of this study suggest that the response is largely impacted by the amount and location of the hazard-independent damage, as well as the complexity of the frame system. Lastly, the study is extended to a three-dimensional steel-frame system. The system is once again perturbed by several cases of nonlinear geometric effects and hazard-independent damage. Results of this study suggest that stability failure is a high concern in the cases considered.


Emphasis: Civil Engineering



To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.