Architectural Engineering Commons^™

Field Evaluation Of Unreinforced Masonry Walls Strengthened With Frp Composites Subjected To Out-Of-Plane Loading, Gustavo Tumialan, Davide Tinazzi, John J. Myers, Antonio Nanni

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Unreinforced masonry (URM) walls at a decommissioned building in St. Louis, Missouri were tested to failure. the walls belonging to the present experimental program were subjected to out-of-plane loading. Previous work on URM and reinforced masonry walls strengthened with FRP laminates has shown remarkable increases in capacity and ductility. However, most of this research has been conducted under laboratory conditions, where, many times, it is a difficult task to represent real field conditions. in this context, this experimental program offered a singular opportunity for performing field experimentation on URM walls strengthened with Glass, Aramid and Carbon Fiber Reinforced Polymers (GFRP, …

Strengthening Of Masonry Structures With Frp Composites, J. Gustavo Tumialan, Francesco Micelli, Antonio Nanni

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Unreinforced masonry (URM) walls are prone to failure when subjected to out-of-plane and in-plane loads. the development of effective and affordable strengthening strategies is a need. in this context fiber reinforced polymer (FRP) materials offer viable solutions to solve or lessen the effects of overloading. This paper describes FRP systems proposed for use in the strengthening of masonry elements as well as the impact of such systems on the building being retrofitted. Also, field applications, some potential and others already implemented applications, are described. Field applications include strengthening for natural hazards (i.e. earthquakes and high wind pressures) as well as …

Multiobjective Optimization Of Seismic Structures, Franklin Y. Cheng, Dan Li, Jeffrey Ger

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper presents a constrained Mult objective optimization method in the form of a robust, practical, problem-independent formulation based on genetic algorithm combined with game theory and investigates the effect of Mult objective optimization on structural design. the study includes objectives, constraints, and design variables as well as their effect on structural design and behavior. the algorithm comprises - Mult objective fitness function, niche method, and Pareto set filter. a 10-story setback building is used to illustrate the evaluation of three choices: steel frame, reinforced concrete frame, composite steel and reinforced concrete frame. Evaluation is based on economics as well …

An Assessment Of In-Situ Frp Shear And Flexural Strengthening Of Reinforced Concrete Joists, Annaiah Raghu, John J. Myers, Antonio Nanni

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study examines the in-situ shear performance and modes of failure of reinforced concrete (RC) T-beams (joists) strengthened with externally bonded carbon fiber reinforced polymer (CFRP) sheets. the experimental program consisted of testing a series of nine structural components at the Malcom Bliss Hospital, in St. Louis, Missouri. the members were tested to validate the different systems and techniques of strengthening. in particular, this paper covers cases of U-Wraps with and without end-anchors. the experimental results clearly indicate the contribution of externally bonded CFRP sheets in increasing the shear capacity of the system. the experimental and theoretical shear strength of …

Overview Of The Japanese Guidelines For Seismic Retrofitting Of Rc Columns Using Frp Materials, Gustavo Tumialan, Hiroshi Fukuyama, Antonio Nanni

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The increasing uses of FRP materials for the strengthening and upgrade of buildings has motivated the international engineering community to produce guidelines for the proper design, handling and installation of the externally bonded FRP systems. Thus, independent efforts coordinated by different organizations such as the Japan Building Disaster Prevention Association (JBDPA) and the American Concrete Institute (ACI) have led to implementing appropriate provisions. the JBDPA guidelines mainly focus on seismic retrofitting of structural elements, which implies the strengthening for shear of deficient structural elements. This paper describes and comments on some of the design approaches provided by the JBDPA guidelines …

Bridge Deck Replacement For Minimum Expected Cost Under Multiple Reliability Constraints, Mark G. Stewart, Allen C. Estes, Dan M. Frangopol

Architectural Engineering

The present paper investigates the effect of limit state selection (strength versus serviceability) on bridge deck life-cycle costs and thus on optimal repair strategies. Such a comparison may then help determine whether safety or functionality (or both) are important criteria when optimizing bridge life-cycle performance and costs. The structural element under consideration is a reinforced concrete bridge deck; namely, a State Highway Bridge in Colorado. Two limit states are considered: ultimate strength and serviceability. The exceedence of either of the limit states considered herein will result in deck replacement; namely, if the reliability index falls below a target reliability index …

Construction Management Internship And Co-Op Programs Stakeholder Needs Assessment.Pdf, Khalid Siddiqi

Faculty Articles

This study analyzes various types of internships and co-op programs offered by universities which are accredited by the American Council of Construction Education ACCE. Practical training requirements for Bachelor of Science BS Construction students and construction companies needs are also assessed. Responses to a questionnaire survey which was administered to program directors of ACCE accredited programs construction firms and construction students provide information about existing types of internship and co-op programs. Student perspective and preferences sought through an internship or co-op position in the Construction Industry were also identified in the study. Construction companies seeking new graduates for employment consider …

Objective And Subjective Evaluation Of The Use Of Directional Sound Sources In Auralizations, Lily M. Wang, Michelle C Vigeant

Durham School of Architectural Engineering and Construction: Faculty Publications

Omni-directional sources are often used in room acoustic computer simulations, as opposed to directional sources, since measured directivity data are quite limited and difficult to obtain.  The purpose of this study is to investigate the objective and subjective significance of adding more complex directivity to the sources used in computer simulations and auralizations.  A simple hall was used as the modelled space in the software program ODEON.  Three source positions on stage and three receiver audience positions were chosen.  Impulse responses (IRs) were calculated for the nine source/receiver combinations, using (a) an omni-directional source, (b) a highly directional source beaming …

Interactions Of Model Detail Level And Scattering Coefficients In Room Acoustic Computer Simulation, Lily M. Wang, Jonathan Rathsam, Steven Ryherd

Durham School of Architectural Engineering and Construction: Faculty Publications

A previous study by the author showed that varying the geometric detail level across a normal range for room acoustic computer modeling has little effect on the results of those computer simulations, if major surfaces in the hall are still constructed accurately.  Scattering coefficients were kept constant across all detail levels.  If one were using lower levels of detail, though, one might assign different material scattering coefficients to compensate for the less mixing geometry.  To study the interaction between model detail level and scattering coefficient selection, three performance spaces in Omaha, Nebraska have been modeled in ODEON at varying levels …

Updating Reliability Of Steel Miter Gates On Locks And Dams Using Visual Inspection Results, Allen C. Estes, Dan M. Frangopol, Stuart D. Foltz

Architectural Engineering

As both reliability analyses and systematic inspection programs for the world’s infrastructure gain increased usage and prominence, it becomes more important to use the information from routine visual inspections to update lifetime reliability assessments and resulting life-cycle inspection/repair strategies. The Army Corps of Engineers currently uses reliability analyses to economically justify the major rehabilitation of navigation structures. This paper illustrates how the Condition Index visual inspections for locks and dams can be modified and used to update the reliability analysis of a steel miter gate. The miter gates on two existing locks and dams along the Mississippi River are used …

Flexural Strengthening Of Bridge Piers Using Frp Composites, Tarek Alkhrdaji, Antonio Nanni

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The effectiveness of FRP jackets for increasing the shear capacity and the flexural ductility of reinforced concrete (RC) columns was demonstrated in many studies. However, for smaller axial loads, the contribution of FRP jackets to flexural strength is minimal. using FRP sheets in the direction of a column with end anchorage to improve its flexural capacity at the base is not easily achieved. This paper reports on a research project aimed at upgrading the flexural capacity of RC piers using near-surface mounted (NSM) FRP rods. Flexural strengthening and testing to failure of the piers were carried out on a bridge …

Accuracy And Interferences For Enzyme-Linked Immunoassay Tests For Atrazine, Craig D. Adams, Hua Jiang, Michael Mcguire, Nicole Graziano, Alan Roberson, Michelle Frey

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Atrazine is one of the most commonly used herbicides in the United States, therefore it is a regulatory concern and is extensively monitored in the environment, especially in drinking water. Because of the higher costs of gas chromatography (GC) methods, utility managers and regulators are considering the increased use of enzyme-linked immunosorbent assay (ELISA) methods for monitoring atrazine. an ELISA test kit was recently approved by the US Environmental Protection Agency. the research in this article points out potential biases and inaccuracies that may occur with such test kits. ELISA test kits for atrazine are typically precise (repeatable) but often …

The Providence River Relocation Project, Architecture Department, Bruner Foundation

Rudy Bruner Award | 30 Years of Urban Excellence

The Providence River Relocation project in Rhode Island’s capital city redirected rivers, overhauled transit infrastructure, and created a new riverfront downtown. Thirty years in the making, the relocation of the Woonasquatucket and Moshassuck rivers, construction of a new rail station, highway interchanges, and twelve bridges restored historical links among Providence’s Capital Center, College Hill, and downtown. The project improved traffic flow in and through downtown and added pedestrian-friendly spaces, including 1.5 miles of river walks, along with a new urban park including a restaurant, amphitheater, fountain, and boat landing.

Redirecting the rivers created new, marketable commercial land without demolishing …

An Improved Optimal Elemental Method For Updating Finite Element Models, Zhongdong Duan, B. F. Spencer, Guirong Yan, Jinping Ou

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Optimal Matrix Method and Optimal Elemental Method Used to Update Finite Element Models May Not Provide Accurate Results. This Situation Occurs When the Test Modal Model is Incomplete, as is Often the Case in Practice. an Improved Optimal Elemental Method is Presented that Defines a New Objective Function, and as a Byproduct, Circumvents the Need for Mass Normalized Modal Shapes, Which Are Also Not Readily Available in Practice. to Solve the Group of Nonlinear Equations Created by the Improved Optimal Method, the Lagrange Multiplier Method and Matlab Function Fmincon Are Employed. to Deal with Actual Complex Structures, the Float-Encoding …