Title: Framework for Quantifying Structural Robustness through Modeling and Simulation
Sponsor: National Science Foundation (NSF)
Project Duration: 2009-2013

Synopsis: Robustness is the ability of a structural system to resist progressive collapse. While research on evaluating structural robustness has been ongoing for a while, many critical questions still remain unanswered. In particular, it is not yet clear what sources of resistance are mobilized during collapse and whether structural robustness can be quantified. To address these questions, the study investigated the robustness of seismically designed steel moment frame buildings using 3-D nonlinear models that were comprehensively validated against experimental data. Simulations studies were then conducted using these models to gain insight into the sources of collapse resistance of the prototype buildings, focusing in particular on the role of composite action between the slab and underlying steel beams and slab membrane action. Emphasis was also placed on identifying the how various types and levels of modeling approximations influenced the computed responses.

Title: Project IBORC: Interaction between Building and Occupant Responses during Collapse
Sponsor: National Science Foundation (NSF)
Project Duration: 2008-2012

Synopsis: The objective of this project is to conduct a multidisciplinary investigation at the intersection of structural engineering, social science, and computer science of how people respond to emergencies. Computational simulation models were developed to represent building collapse (the hazard) and human egress (the response). Agent Based Models (ABMs) were used to model human behavior. ABM is a computational simulation methodology used to build an artificial society. The simulation is populated with computer-driven agents that have their own characteristics, are different from others, and are adaptive and capable of interacting with each other and with their environment. The interactions of interdependent agents generate complex systems, usually understood as emergence, that otherwise could not be obtained through the addition of the parts. ABM provides information relevant to the conduct of experiments for which real-world data collection would be unethical, impractical, or prohibitively expensive, hence its use for the proposed work. A new ABM was developed in this project in collaboration with the Disaster Research Center at the University of Delaware. The newly developed model is one of the first to incorporate group social behavior. Most existing models to date are based upon the "sole actor" model, where every person makes selfish evacuation decisions based on self-preservation. Current social science theories have disproved the so-called panic egress mode, and indicate that people interact socially during evacuation. Agents embedded within models of collapsing buildings were used to investigate how people response during extreme situations.

Title: Characterizing High-Strain-Rate Response of Cementitious Composites Using a Novel Strain-Energy-Based Impact Test System
Sponsor: National Science Foundation (NSF)
Project Duration: 2008-2011

Synopsis: A novel test system was proposed for characterizing the high-strain-rate response of materials. The new method exploits the internal strain energy accumulated in an elastic bar to impart a high speed, high energy pulse onto a specimen. The new test system overcomes the combined limitations of traditional impact test setups and enables high quality impact testing in a scalable, cheap, compact, fast and safe manner. Another critical advantage is the ability to test with a small set-up, relatively large size specimens, which permits tests that more truly represent the behavior of non-homogenous building materials. Fundamental research was conducted to optimize and explore the capabilities of the new system.

Title: Rapid Post-Disaster Reconnaissance for Building Damage Using Augmented Situational Visualization and Simulation Technology
Sponsor: National Science Foundation (NSF)
Project Duration: 2007-2011

Synopsis: This project investigated methods for using Augmented Reality (AR) to evaluate earthquake-induced building damage. Previously stored building information was superimposed onto the view of a real structure in AR and structural damage could be quantified by measuring and interpreting key differences between the real and augmented views. Proof-of-concept experiments were performed to demonstrate the feasibility of the proposed technology. Reduced computational models were also developed that could run rapidly enough to be used for in-situ evaluations of structural response.

Title: NEESR-SG: Innovative Applications of Damage Tolerant Fiber-Reinforced Cementitious Materials for New Earthquake-Resistant Structural Systems and Retrofit of Existing Structures
Sponsor: National Science Foundation (NSF)
Project Duration: 2005-2010

Synopsis: This project focused on developing a better understanding of the inelastic cyclic response of structures comprised of high performance fiber reinforced cementitious composites (HPFRCCs). HPFRCCs are a class of materials that are ductile in tension, do not spall in compression, behave like a confined concrete, and capable of providing confinement to normal reinforcement. In addition to enhancing confinement and flexural behavior in plastic hinging regions, HPFRCC materials are capable of providing ductility and energy dissipation capabilities to shear critical members that are normally a difficult design issue for RC structures. The project contained several phases: development of a commercially viable HPFRCC, testing of components and system, development of novel computational tools and simulation of system response to seismic excitation.

Title: Improving USAR Preparedness using Simulation Technology
Sponsor: National Science Foundation (NSF)
Project Duration: 2005-2008

Synopsis: When a building collapses due to a catastrophic event, stable voids are inevitably formed in the rubble pile. These voids occur as a result of falling structural and nonstructural elements that interact together in a favorable manner to create spaces in which victims may find shelter. Since as many as one third of all building collapse victims that are rescued are found in such spaces, the primary objective of this research was to use state-of-the-art finite element simulations to investigate how, and under what conditions, they are formed. The project employed detailed finite element simulations coupled with virtual reality visualization techniques.

Title: Development of an Enhanced Pushover Procedure for Performance-Based Seismic Evaluation Of Buildings
Sponsor: National Science Foundation (NSF)
Project Duration: 2002-2006

Synopsis: This project investigated inter-story drift and failure mechanisms that control the design of a structural system through a detailed study of various types of pushover techniques. The study was carried out on a selected group of six existing buildings for which instrumented data from recent earthquakes was available. The building models used in the analyses were calibrated to measured response thereby ensuring the reliability of the evaluation exercises. These evaluation tasks were conducted in two phases: the first focused on evaluating existing procedures, and the second phase an improved multi-mode and adaptive pushover technique.

Title: Vulnerability of Bridge Piers to Collision by Heavy Vehicles
Sponsor: National Science Foundation (NSF)
Project Duration: 2003-2005

Synopsis: Accidental or malevolent vehicle/pier collisions can have serious implications both in terms of loss of human lives and damage to the transportation system and economy. This project employed detailed finite element simulation to study the effect of vehicle collision with various types of bridge piers. The vehicles were crashed into the piers at various speeds and the effect of the collision on the bridge piers evaluated. The results of this study were used to assess the then current AASHTO provisions for bridge design.

Title: Seismic Behavior and Design of Hybrid Wall Systems
Sponsor: National Science Foundation (NSF)
Project Duration: 1999-2004

Synopsis: This research focused on developing a better understanding of the seismic response of hybrid wall systems through detailed inelastic dynamic analyses. Two types of hybrid wall systems were considered, a) structural systems comprised of solid or perforated reinforced concrete shear walls and steel moment frames, and b) structural systems comprised of steel-girder-coupled shear walls and steel moment frames. The proposed project focused on the development of an existing finite element program to account for wall finite elements capable of simulating the complex behavior of wall panels. Prototype systems were designed using then existing provisions and subjected to suites of seismic excitation to study their response to strong shaking. The simulations focused on identifying the optimal degree of coupling between coupled shear walls and shed light on the interaction between shear walls and moment frames, established design oriented methods for determining the distribution of forces in the walls and frames, and assessed then current provisions for the design of hybrid wall systems and their components.

Title: Large Scale Structural Research Laboratory Equipment
Sponsor: National Science Foundation (NSF)
Project Duration: 1998-2000

Synopsis: This project focused on obtaining equipment for the new Structures lab in the UCF Department of Civil and Environmental Engineering. The then new high bay lab had 40 ft high clearance, 3000 square feet of lab area, and a 6' deep 25' x 50' strong floor. The equipment purchased included: 1) two 100-kip servo-controlled actuators (MTS model 243.45T with 20" stroke), 60 gpm MTS hydraulic pump and an MTS control system; 2) 128-channel data acquisition system, 3) 200-kip Satec Universal Testing Machine, 4) 20-ton overhead crane; 5) steel reaction frame; and 6) several computers, hydraulic jacks, load cells, and other miscellaneous handling and testing equipment.