Civil and Environmental Engineering Commons^™

Improving Prediction Accuracy In Mechanistic-Empirical Pavement Design Guide, Scott Schram, Magdy Abdelrahman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Model calibration plays a fundamental role in the implementation of the mechanistic-empirical pavement design guide. The data used in the default calibration effort, which were afforded by the Long Term Pavement Performance (LTPP) database, have a network-level inference space. As implementation proceeds, state highway agencies may be inclined to calibrate at a local network level. However, with a focus on the calibration data set to local project-level conditions, model prediction error can be reduced further. Under this study, Nebraska Department of Roads Pavement Management System data were used to calibrate two design guide smoothness models at the local project level. …

Cost-Effective, Structural Stay-In-Place Formwork System Of Fiber-Reinforced Polymer For Accelerated And Durable Bridge Deck Construction, Thomas E. Ringelstetter, Lawrence C. Bank, Michael G. Oliva, Jeffrey S. Russell, Fabio Matta, Antonio Nanni

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper describes research on the evolution of a cost-effective, structural stay-in-place (SIP) formwork bridge deck system with an integrated modular three-dimensional fiber-reinforced polymer (FRF) reinforcement cage. Recent research conducted at the University of Wisconsin is reviewed to show the evolution of the reinforcing system to include an integral FRP SIP form. the evolution occurred through laboratory testing, which was followed by the design and construction of two bridge structures owned by the State of Wisconsin. Each structure used different FRP reinforcement and formwork. These projects pointed out the need for a competitive SIP formwork to be used in conjunction …

Effectiveness Of Open-Graded Base Layer On Subgrade Moisture Regime And Overall Pavement Performance, Hassan Salem, Fouad Bayomy, Robert Smith, Magdy Abdelrahman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Rockcap (open-graded crushed aggregate with a nominal maximum size of 2.5 in.) base layer is commonly used in the construction of asphalt pavements in Idaho. The effectiveness of the rockcap layer on the subgrade moisture regime and the overall pavement performance were evaluated. Two pavement sites were selected in northern and southern regions of the state. At each site, two pavement sections that are identical and adjacent to each other were instrumented by temperature, frost, and moisture sensors using time domain reflectometry (TDR) probes. One was constructed by a well-graded 3/4-in. aggregate base, whereas the other was constructed by the …

Systems Approach For Estimating Field Moisture Content, Thomas M. Petry, Yuh-Puu Han, David Newton Richardson

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper describes a software tool developed for estimation of the field moisture content of subgrade materials. Subgrade behavior is directly related to its moisture content. Unfortunately, some approaches of estimating field moisture content are too complex to be used in routine design. In this paper, the authors attempt to provide an approach that is easy to use. The software presented here was developed using expert system approaches. It is capable of analyzing data entered by the users, and providing estimations to meet different scenarios. The information entered by the user is first examined for its reasonableness and accuracy. Then, …

Transverse-Earthquake Induced Deformations Of A Bridge Approach Embankment In The New Madrid Seismic Zone, Wanxing Liu, Richard Wesley Stephenson, Ronaldo Luna

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

It is predicted that strong earthquakes, larger than M 7.0, may occur within next 50 years in the New Madrid Seismic Zone (NMSZ), the location of three of the most powerful earthquakes in United States history. Large displacements may occur during strong earthquakes that can cause an embankment to fail or lose its function. The hyperbolic stress-strain model with Masing rules was modified to account for strength and stiffness reduction due to change in the effective confining pressure. The Byrne model was combined with a hyperbolic model to calculate the pore water pressure caused by seismic shaking. This modified hyperbolic …

Separation And Quantification Of N-Acetylcysteine-Amide (Naca) By Hplc With Fluorescence Detection, Wei Wu, Glenn Goldstein, Craig D. Adams, Richard H. Matthews, Nuran Ercal

Chemistry Faculty Research & Creative Works

N-acetyl-l-cysteine (NAC) is a well-known antioxidant that is capable of facilitating glutathione (GSH) biosynthesis and replenishing intracellular GSH under oxidatively challenging circumstances. N-acetyl-cysteine-amide (NACA), the amide form of NAC, is a newly designed and synthesized thiol-containing compound which is believed to be more lipophilic and permeable through cell membranes than NAC. The metabolic and antioxidant effects of these compounds in vitro and in vivo are under investigation. However, an analytical method that can separate and quantify both compounds simultaneously is not yet available, to the best of our knowledge. Because of their structural similarities, the two compounds are difficult to …

Dynamic Growth Rates Of Microbial Populations In Activated Sludge Systems, Peter George Stroot, Pascal E. Saikaly, Daniel B. Oerther

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Results of mathematical modeling and whole cell 16S ribosomal RNA-targeted fluorescence in situ hybridizations challenge the widely held perception that microbial populations in "steady-state" activated sludge systems share a common net growth rate that is proportional to the inverse of the mean cell residence time. Our results are significant because they encourage bioprocess engineers to appreciate the differences in growth physiology among individual microbial populations in complex mixed microbial communities such as suspended growth activated sludge bioreactor systems.

Use Of 16s Rrna Gene Terminal Restriction Fragment Analysis To Assess The Impact Of Solids Retention Time On The Bacterial Diversity Of Activated Sludge, Pascal E. Saikaly, Peter George Stroot, Daniel B. Oerther

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Terminal restriction fragment length polymorphism (T-RFLP) analysis of 16S rRNA genes was used to investigate the reproducibility and stability in the bacterial community structure of laboratory-scale sequencing batch bioreactors (SBR) and to assess the impact of solids retention time (SRT) on bacterial diversity. Two experiments were performed. In each experiment two sets of replicate SBRs were operated for a periods of three times the SRT. One set was operated at an SRT of 2 days and another set was operated at an SRT of 8 days. Samples for T-RFLP analysis were collected from the two sets of replicate reactors. HhaI, …

Strength Of Cfs Floor Assemblies With Clip Angle Bearing Stiffeners, S. R. Fox

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

No abstract provided.

Experimental Evaluation Of The Strength And Behaviour Of 16- And 18-Gauge Cold Formed Steel Top Track Systems, J. L. Dawe

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

No abstract provided.

Cold-Formed Steel Walls With Fiberboard Sheathing - Shear Wall Testing, Nahb Research Center, Inc.

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

No abstract provided.

Nonhydrostatic And Nonlinear Contributions To The Energy Flux Budget In Nonlinear Internal Waves, S. K. Venayagamoorthy, O. B. Fringer

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

We use high-resolution two-dimensional simulations to model the generation, and evolution of nonlinear internal waves formed as a result of the interaction of a first-mode internal wave field with idealized slopes. The derivation of the energy equation and the energy flux terms are presented. By employing an analysis of the distribution of the energy flux across the shelf break, we quantify the contributions to the energy flux budget from nonhydrostatic as well as nonlinear effects in comparison to the contribution from the baroclinic pressure anomaly term used widely for linear internal waves. Our results show that the contributions to the …

Novel Distributed Cable Sensors For Detection Of Cracks In Rc Structures, Genda Chen, David Pommerenke

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In this paper, the development of a fundamentally new, topology-based cable sensor design concept is summarized for crack detection in reinforced concrete (RC) structures. The sensitivity, spatial resolution, and signal loss of sensors are investigated both numerically and experimentally. Two sensors were fabricated and validated with small- and large-scale laboratory tests under different loads. Both were proven sensitive to crack of various sizes from visually undetectable to excessive, giving the location and severity of damage simultaneously. One sensor has been installed on a three-span bridge for its long-term monitoring. It is capable of recording damage that has occurred during a …

Ccfss Technical Bulletin Fall 2005, Wei-Wen Yu Center For Cold-Formed Steel Structures

CCFSS Technical Bulletins (1993 - 2020)

No abstract provided.

Ccfss News Fall 2005, Wei-Wen Yu Center For Cold-Formed Steel Structures

CCFSS Newsletters (1999 - 2008)

No abstract provided.

Key Seismic Design Parameters: Steel And Wood Light-Frame Shear Walls, Coheen & Associates Structural Engineering

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

No abstract provided.

Revised Asce Specification For The Design Of Cold-Formed Stainless Steel Structural Members, Shin Hua Lin, Wei Wen Yu, Theodore V. Galambos, Edward Wang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Since the publication of the first edition of the AISI specification for the design of light gage cold-formed stainless steel structural members in 1968 [Specification for the design of light gage cold-formed stainless steel structural members. 1968 ed. American Iron and Steel Institute (AISI); 1968], cold-formed stainless-steel members have been increasingly used in building construction and other structural applications due to their superior corrosion resistance, ease of maintenance, pleasing appearance, and high strength. in 1990, the first ASCE standard, ANSI/ASCE-8-90 [Specification for the design of cold-formed stainless steel structural members (ANSI/ASCE 8-90). American Society of Civil Engineers (ASCE); 1991], was …

Damage Localization In Ambient Vibration By Constructing Proportional Flexibility Matrix, Zhongdong Duan, Guirong Yan, Jinping Ou, B. F. Spencer

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Damage Localization Approaches based on Changes of Flexibilities Constitute an Important Technique for Damage Detection. However, the Unavailability of Flexibility Matrix with Output-Only Data Makes Flexibility-Based Approaches Not Really Applicable in the Very Important Cases of Ambient Vibrations. an Algorithm is Presented to Construct a Proportional Flexibility Matrix (PFM) from a Set of Arbitrarily Scaled Tested Modal Shapes and Modal Frequencies. the Constructed PFM is Just within a Scalar Multiplier to the Real Flexibility Matrix, and the Scalar Multiplier is Theoretically the First Modal Mass, Which is Undetermined Before the Mode is Properly Scaled. Instead of Real Flexibilities, the PFMs …

Investigating Student Interest In Post-Secondary Stem Education, Anant R. Kukreti, Shafiqul Islam, Daniel B. Oerther, Karen C. Davis, Mark G. Turner, Catherine V. Maltbie, Thaddeus W. Fowler

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Interest among students for post-secondary STEM education and causes behind the declining enrollment rate was analyzed. A K-12 survey was developed at the University of Cincinnati to gather information directly from students to verify the teachers' statements regarding K-12 students' perceptions of the engineering profession and studying engineering in college. The K-12 student survey respondents indicated that about 28% of the 6-12 graders were interested in engineering. The survey also showed that students wanted to be an engineer because it was a stable living.

Failure Investigation Of The Steel Strut Of Paseo Suspension Bridge, Genda Chen, Chris Courtright, Lokeswarappa R. Dharani, B. Xu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A vertical strut of the 1232-foot long, self-anchored Paseo Suspension Bridge fractured when the temperature hit at a record low of 9°F below zero. During inspection the following day, it was found that its lower pin was frozen and did not allow for free movement of the superstructure. The objective of this study is to pinpoint one of the four reasons for this incidence or their combination: overstressing, thermal contraction, fatigue, and reduction in fracture toughness at low temperatures. To achieve this objective, material property and fatigue testing was performed on samples of strut material while the bridge and strut …

Aisi Standard For Cold-Formed Steel Framing – Truss Design, 2004 Edition, American Iron And Steel Institute

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

The material contained herein has been developed by the American Iron and Steel Institute Committee on Framing Standards. The Committee has made a diligent effort to present accurate, reliable, and useful information on cold-formed steel framing design and installation. The Committee acknowledges and is grateful for the contributions of the numerous researchers, engineers, and others who have contributed to the body of knowledge on the subject. Specific references are included in the Commentary. With anticipated improvements in understanding of the behavior of cold-formed steel framing and the continuing development of new technology, this material may eventually become dated. It is …

Standard For Cold-Formed Steel Framing - Truss Design, 2004 Edition, American Iron And Steel Institute

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

The material contained herein has been developed by the American Iron and Steel Institute Committee on Framing Standards. The Committee has made a diligent effort to present accurate, reliable, and useful information on cold-formed steel framing design and installation. The Committee acknowledges and is grateful for the contributions of the numerous researchers, engineers, and others who have contributed to the body of knowledge on the subject. Specific references are included in the Commentary.

With anticipated improvements in understanding of the behavior of cold-formed steel framing and the continuing development of new technology, this material may eventually become dated. It is …

Aisi Standard For Cold-Formed Steel Framing – Header Design, 2004 Edition, American Iron And Steel Institute

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

The material contained herein has been developed by the American Iron and Steel Institute Committee on Framing Standards. The Committee has made a diligent effort to present accurate, reliable, and useful information on cold-formed steel framing design and installation. The Committee acknowledges and is grateful for the contributions of the numerous researchers, engineers, and others who have contributed to the body of knowledge on the subject. Specific references are included in the Commentary. With anticipated improvements in understanding of the behavior of cold-formed steel framing and the continuing development of new technology, this material may eventually become dated. It is …

Standard For Cold-Formed Steel Framing- Lateral Design, 2004 Edition, American Iron And Steel Institute

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

The material contained herein has been developed by the American Iron and Steel Institute Committee on Framing Standards. The Committee has made a diligent effort to present accurate, reliable, and useful information on cold-formed steel framing design and installation. The Committee acknowledges and is grateful for the contributions of the numerous researchers, engineers, and others who have contributed to the body of knowledge on the subject. Specificreferences are included in the Commentary.

With anticipated improvements in understanding of the behavior of cold-formed steel framing and the continuing development of new technology, this material may eventually become dated. It is anticipated …

Standard For Cold-Formed Steel Framing-Header Design, 2004 Edition, American Iron And Steel Institute

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

The material contained herein has been developed by the American Iron and Steel Institute Committee on Framing Standards. The Committee has made a diligent effort to present accurate, reliable, and useful information on cold-formed steel framing design and installation. The Committee acknowledges and is grateful for the contributions of the numerous researchers, engineers, and others who have contributed to the body of knowledge on the subject. Specific references are included in the Commentary.

With anticipated improvements in understanding of the behavior of cold-formed steel framing and the continuing development of new technology, this material may eventually become dated. It is …

Behavior And Fatigue Properties Of Metallic Dampers For Seismic Retrofit Of Highway Bridges, Genda Chen, Stephen Eads

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The objective of this study is to develop an economical solution with metallic dampers for the seismic retrofit of highway bridges in low occurrence seismic zones, such as in the Central and Eastern United States. Select low carbon steel rods were first tested for their ductile behavior and material strength. Large-scale, tapered rods were then tested for their energy dissipation capability and fatigue strength under regular, irregular, and earthquake loads. A full-scale damper made of five tapered rods was designed next for the seismic retrofit of a three-span continuous steel-girder bridge in southeast Missouri; its system performance including joints and …

Lessons Learned From Failures Of The Building Envelope In Windstorms, Joseph E. Minor

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Lessons learned from failures of the building envelope in windstorms are encapsulated in three principal findings. the building envelope is crucial to the performance of buildings in windstorms. Windborne debris is decisive in shaping the performance of the building envelope. Design attention should be given to postimpact behavior of building-envelope systems. Reviews of damage documentation, insurance records, and computer simulations of building failures establish the importance of the building envelope to satisfactory building performance. These reviews also establish the decisive role of windborne debris in causing damage. the imperative for considering the postimpact behavior of building envelope systems is discussed, …

Cold-Formed Steel Gable End Wall Design Using The Prescriptive Method For One And Two Family Dwellings, Benjamin W. Downey, Sutton F. Stephens, Roger A. Laboube

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

No abstract provided.

Ccfss Technical Bulletin Spring 2005, Wei-Wen Yu Center For Cold-Formed Steel Structures

CCFSS Technical Bulletins (1993 - 2020)

No abstract provided.

Ccfss News Spring 2005, Wei-Wen Yu Center For Cold-Formed Steel Structures

CCFSS Newsletters (1999 - 2008)

No abstract provided.