Engineering Commons^™

Collaborative Research: An Integrated Microstructure-Based Approach To Property Prediction For Cement-Based Materials, Eric N. Landis

University of Maine Office of Research Administration: Grant Reports

The project is a collaborative effort between the research groups at the University of Maine and the University of California, Davis. It represents a convergence of 3D micro-structural imaging with discrete element computational modeling to address the need for quantitative links between salient micro-structural properties and bulk material performance. High-resolution 3D images of material microstructure will be produced using x-ray microtomography (XMT). These images will be used to examine the micromechanical response of cement composites to mechanical loading and drying shrinkage. 3D deformation fields and internal crack distributions will be measured at selected loading stages and correlated with the spatial …

Product Technical Information, Steel Stud Manufacturers Association

CCFSS Library (1939 - present)

No abstract provided.

Cold-Formed Steel Framing Seismic Design Optimization Phase 1a: Seismic Equivalency Parameter Evaluation, American Iron And Steel Institute

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

No abstract provided.

Reliability Estimation Of Complex Numerical Problems Using Modified Conditional Expectation Method, Christopher D. Eamon, Bulakorn Charumas

Civil and Environmental Engineering Faculty Research Publications

A simulation-based structural reliability analysis method is presented. It is intended as an alternate approach to estimate reliability for problems for which most-probable point of failure methods fail and when computational resources are limited. The proposed method combines conditional expectation and estimating the PDF or CDF of a selected portion of the limit state. In the proposed approach, complex limit state functions are simplified to two random variable problems. The success of the simplification depends on the quality of the CDF estimate. Results indicate that the method may provide accurate and efficient solutions for some difficult reliability problems.

Coated Steel Rebar For Enhanced Concrete-Steel Bond Strength And Corrosion Resistance, Genda Chen, Jeffery S. Volz, Richard K. Brow, Dongming Yan, Signo Tadeu Dos Reis, Chenglin Wu, Fujian Tang, Charles R. Werner, Xing Tao

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This report summarizes the findings and recommendations on the use of enamel coating in reinforced concrete structures both for bond strength and corrosion resistance of steel rebar. Extensive laboratory tests were conducted to characterize the properties of one- and two-layer enamel coatings. Pseudostatic tests were performed with pullout, beam and column specimens to characterize mechanical properties and develop design equations for the development length of steel rebar in lap splice and anchorage areas. The splice length equation was validated with the testing of large-scale columns under cyclic loading. For corrosion properties, ponding, salt spray, accelerated corrosion, potentiodynamic and electrochemical impedance …

Constructability Testing Of Folded Plate Girders, Luke A. Glaser

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

A new steel girder bridge system was developed at the University of Nebraska. The innovative girder design is a box girder folded from a single steel plate that has a trapezoid shape with an opening on the bottom. The girder has application in short span bridges and accelerated construction situations. The structural performance of the girder requires investigation in all stages of a bridge’s lifecycle. This thesis contains descriptions and results from the first two tests from a series of tests developed to evaluate this new girder shape. The objective of these two tests was to investigate the constructability of …

Experimental Investigation Of Folded Plate Girders And Slab Joints Used In Modular Construction, Kyle A. Burner

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

The folded plate girder, a newly proposed bridge girder, is investigated through this thesis. The folded plate girder is cold bent out of a single sheet of steel. The cold bending eliminates the costly and inconsistent shop welds found in traditional girders. The folded plate girder is meant for application in short span bridges. The girder was subjected to an equivalent 75 year lifetime loading to investigate the fatigue performance.

The rebar detail used in the closure region between adjacent slabs has been investigated in the past by the NCHRP 12-68 project. This thesis will proposes a hooked rebar detail …

Supplement No. 2 To The North American Specification For The Design Of Cold-Formed Steel Structural Members, 2007 Edition, American Iron And Steel Institute

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

No abstract provided.

Modelling And Verification Of Response Of Rc Slabs Strengthened In Flexure With Mechanically Fastened Frp Laminates, Annalisa Napoli, Fabio Matta, Enzo Martinelli, Antonio Nanni, Roberto Realfonzo

Faculty Publications

Mechanically fastened fibre-reinforced polymer laminate systems are emerging as a promising means for the repair and strengthening of reinforced concrete members. This technology entails the use of pultruded carbon- and glass- vinyl ester fibre-reinforced polymer laminates with enhanced longitudinal bearing strength that are connected to the concrete substrate by means of steel anchors. Attractive applications are those for emergency repairs where constructability and speed of installation are critical requirements. In this paper, an experimental investigation is first presented that included laboratory testing of scaled reinforced concrete slabs strengthened with four different combinations of laminate lengths and fastener layouts to study …

Intricacies Of Professional Certifications For Quality Management (Qm), Edmund R. Martelli

Masters Theses & Specialist Projects

The modern manufacturing marketplace is extremely complex and constantly changing. Career professionals often seek job placement, career advancement, and continuing education through professional certifications. Professional certifications in the United States (U.S.) have been evolving since 1911. In the 1950s, engineering groups established professional certifications and licenses. In the 1980s, administration of accreditation of certification programs proliferated, and by the 1990s, many government and professional organizations sought to standardize procedures for the industry. Currently, professional certifications are available for virtually every profession and issued by multitudes of organizations.

Quality management (QM) encompasses an extensive combination ofprofessional abilities. Providers of professional certifications …

Failure Literacy In Structural Engineering, Norbert J. Delatte

Civil and Environmental Engineering Faculty Publications

The history of the development of practice in many engineering disciplines is, in large part, the story of failures, both imminent and actual, and of the changes to designs, standards and procedures made as the result of timely interventions or forensic analyses. All engineers, and more particularly structural engineers, should be failure literate. Failure literacy means knowing about the critical historical failure cases that have shaped the profession: not merely the surface technical details, but the environment, the communications difficulties and the procedural issues. In the US, an intensive effort has been under way for nearly a decade to promote …

Simplified Procedures For Seismic Analysis And Design Of Piers And Wharves In Marine Oil And Lng Terminals, Rakesh K. Goel

Civil and Environmental Engineering

No abstract provided.

Report On Laboratory Testing Of Anchor Bolts Connecting Cold-Formed Steel Track To Concrete With Minimum Edge Distances, American Iron And Steel Institute

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

No abstract provided.

Siding Attachment To Cold-Formed Steel Walls Through Varying Layers Of Foam Insulation, Newport Ventures, Inc., Applied Residential Engineering Services

CCFSS Library (1939 - present)

When insulating an exterior wall, more and more codes are requiring continuous insulation on the exterior of the studs to reduce the effect of thermal bridging. As energy codes continue to become more stringent, the thickness of the continuous installation has increased. Although wood and steel are both impacted, the requirements generally are higher for steel framing.

A significant implementation challenge caused by increasingly higher levels of continuous insulation is the lack of specifications for the type of fastener and siding installation details that should be used when installing thicker levels of insulation. Thus, the engineer, architect, builder, and contractor …

Achieving The Vision Through High Ethical Standards, Sarah E. Bertke

Ohio Valley Regional Student Conference

No abstract provided.

Input-Output Analysis Of Irish Construction Sector Greenhouse Gas Emissions, Adolf Acquaye, Aidan Duffy

Articles

Ireland is committed to limiting its greenhouse gas (GHG) emissions to 113% of 1990 levels over the period 2008-12 and to 84% of 2005 levels by 2020 under the Kyoto Agreement and the EU’s ’20 20’ by 2020 respectively. National policies have targeted many industry sectors but have failed to directly tackle GHG emissions associated with construction activity. This paper estimates energy and GHG emissions intensities of the Irish construction sector and subsectors and estimates its contribution to Irish national emissions. This information is used to identify and assess the impacts of policy measures which would result in a reduction …

Cold-Formed Steel Bolted Connections Using Oversized And Slotted Holes Without Washers, Phase 2, American Iron And Steel Institute

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

No abstract provided.

North American Standard For Cold-Formed Steel Framing -- Lateral Design, 2007 Edition With Supplement No 1. October 2009 (Reaffirmed 2012), American Iron And Steel Institute

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

No abstract provided.

Simulation Of Traffic Loading On Highway Bridges, Bernard Enright

Other resources

This work is based on weigh-in-motion measurements for approximately three million trucks obtained from sites in five European countries. Techniques have been developed, supported by photographic evidence, for filtering the measurements to identify and remove unreliable values, and for the classification of extremely heavy vehicles. The collected measurements have been used as the basis for building and calibrating a Monte Carlo simulation model for bridge loading. Two-lane traffic is simulated – either two lanes in the same direction or one lane in each direction. The model allows for vehicles that are both heavier and have more axles than in the …

Design, Construction And Load Testing Of The Bridge On Arnault Branch, Washington County, Missouri Using Innovative Technologies, Dongming Yan, Genda Chen, Nestore Galati, Sahra Sedigh

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The superstructure and instrumentation designs of a three-span bridge are presented in this report. The three spans include a precast box-girder bridge, a precast deck on steel girder and a precast deck on concrete girder. They were designed to compare the performance of various bridge decks reinforced with fiber reinforced polymers (FRP) through field instrumentations. A wireless monitoring system was designed to facilitate the collection of field data after the completion of bridge construction. The collected data will allow the study of FRP bars and stay-in-place FRP grid systems.

Design And Evaluation Of Steel Bridges With Double Composite Action, Rajan Sen, Steven Stroh, Niranjan Pai, Purvik Patel, Dennis Golabek

Civil and Environmental Engineering Faculty Publications

This report presents findings from a cooperative USF/URS/FDOT research study undertaken to develop design rules for double composite steel bridges. In the study, a 48 ft long, 16 ft wide, 4 ft. 10⅛ in. deep trapezoidal HPS 70W box section designed to AASHTO’s LRFD 2004 specifications was fabricated and tested. The section has an 8 in. thick top slab and a 7 in. thick bottom slab and represented the entire negative moment region of a full-size, continuous bridge. The specimen was tested to evaluate fatigue, service and ultimate provisions of the AASHTO code. Instrumentation was provided to monitor load, strain, …

Development Of Innovative Load Transfer Mechanism To Reduce Hurricane-Induced Failures In New And Existing Residential Construction, Sheikh Saad Ahmed

FIU Electronic Theses and Dissertations

Implicit in current design practice of minimum uplift capacity, is the assumption that the connection's capacity is proportional to the number of fasteners per connection joint. This assumption may overestimate the capacity of joints by a factor of two or more and maybe the cause of connection failures in extreme wind events. The current research serves to modify the current practice by proposing a realistic relationship between the number of fasteners and the capacity of the joint. The research is also aimed at further development of non-intrusive continuous load path (CLP) connection system using Glass Fiber Reinforced Polymer (GFRP) and …

Development Of Canadian Seismic Design Provisions For Steel Sheathed Shear Walls, Nisreen Balh

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

No abstract provided.

Historic Bridge Evaluation Using Finite Element Techniques, Helena M. Charron

Masters Theses 1911 - February 2014

The present study examined the application of modern, computer-based analysis methods to two existing historic bridges in Massachusetts. The first bridge featured in this study is the Woronoco Bridge, a reinforced concrete open spandrel arch bridge that was constructed in 1923. It was hoped that a computer-based, parametric study of this bridge would prove it to be deck-stiffened, similar to select bridges of Swiss engineer Robert Maillart. However, the results do not support that there was any intent to reduce bending in the arch as a result of increasing the stiffness of the bridge deck. Instead, the Woronoco Bridge appears …

Investigation Of The Behavior Of Open Cell Aluminum Foam, Patrick J. Veale

Masters Theses 1911 - February 2014

The study investigates the behavior open cell aluminum foam in scenarios applicable to potential use in structural applications. Behavior was examined through mechanical testing, computer modeling and analytic expressions. Existing assumptions about the foam characteristics that define the elastic properties were expanded to include contributions of axial and shear deformations in addition to bending and were rewritten in terms of the axial and bending stiffness ratios of ligaments. Compressive and tensile tests were performed to gain a measure of the elastic properties of the foam as well as the behavior and failure mechanisms in both loading conditions. The materials used …

Material Characterization And Structural Response Of Historic Truss Bridges, Sean L. Kelton

Masters Theses 1911 - February 2014

Historic truss bridges are examined in this thesis through material characterization of wrought iron and structural evaluation of an early 20th century pony truss bridge. The mechanical properties of wrought iron from six 19th century truss bridges were evaluated through mechanical testing that includes hardness and tension tests. The main findings of this work are: 1) That hardness is a poor predictor of yield and ultimate stress but has some ability in screening iron for iron with low ductility, 2) there is a statistically significant difference in the distribution of yield and ultimate stresses between material samples from different bridges, …

Earthquake Engineering Simulation With Flexible Cladding System, Jun Jie Li

Masters Theses 1911 - February 2014

This research investigates the interaction between heavy precast cladding units attached to steel framed buildings. Cladding systems are designed as non-structural components and are not expected to contribute to the energy absorption of the primary structure. However, research has indicated that the cladding system may be designed to reduce the response of the primary structure under seismic excitations. The use of flexible connections between the cladding and primary structural frames may be able to provide beneficial effects to the entire structural response. In this study, a series of earthquake engineering simulations were conducted in OPENSEES to analyze the effects of …

Studies Of Dynamic Crack Propagation And Crack Branching With Peridynamics, Youn Doh Ha Ph.D., Florin Bobaru Ph.D.

Department of Engineering Mechanics: Faculty Publications

In this paper we discuss the peridynamic analysis of dynamic crack branching in brittle materials and show results of convergence studies under uniform grid refinement (m-convergence) and under decreasing the peridynamic horizon (δ-convergence). Comparisons with experimentally obtained values are made for the crack-tip propagation speed with three different peridynamic horizons.We also analyze the influence of the particular shape of themicro-modulus function and of different materials (Duran 50 glass and soda-lime glass) on the crack propagation behavior. We show that the peridynamic solution for this problem captures all the main features, observed experimentally, of dynamic crack propagation and branching, as well …

Estimating The Characteristic Vertical Response Of A Flexible Footbridge Due To Crowd Loading, Joe Keogh, Colin C. Caprani, Paul Archbold, Paul Fanning

Conference papers

The issue of excessive vibration of footbridges due to pedestrian loading is now well documented. Bridge vibrations produced from a crowd of pedestrians have been estimated by modifying the effect caused by a single pedestrian by an enhancement factor to take crowd synchronization into account. In this paper this approach is extended to account for the fact that all pedestrians will not have the same pacing frequencies, and the effects of distributions of pacing frequency and other parameters on the enhancement factor are investigated. It is shown that this more faithful representation of pedestrian crowd walking behaviour gives reduced vibration …

A New Congested Traffic Load Model For Highway Bridges, Colin C. Caprani, Colm Carey, Bernard Enright

Conference papers

Long span highway bridges are critical components of any nation’s infrastructure. Therefore accurate assessment of highway bridge loading is essential, and it is well known that congested traffic governs load effect for such bridges. Current congestion models use conservative assumptions about traffic and inter-vehicle gaps. This research investigates congested traffic flow through the use of traffic microsimulation which has the ability to reproduce complex traffic phenomena based on driver interactions. A time series model has been developed to produce a speed time-series similar to the results of the microsimulation. The speed time-series from the new model, combined with the established …