Structural Engineering Commons^™

Post-Earthquake Reconnaissance Report On Transportation Infrastructure Impact Of The February 27, 2010, Offshore Maule Earthquake In Chile, Wen-Huei Phillip Yen, Genda Chen, Ian G. Buckle, Tony M. Allen, Daniel E. Alzamora, Jeffrey Ger, Juan G. Arias

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This report documents the findings and lessons learned from the February 27, 2010, M8.8 offshore Maule earthquake in Chile. Fewer than 0.15 percent of the bridges in Chile's inventory, most built after 1995, collapsed or suffered damage that rendered them useless. Many spans of precast prestressed discontinuous girder bridges with continuous decks fell off their supports, probably due to significant in-plane rotation of the superstructure as a result of severe shaking. Lateral steel stoppers used to provide both vertical and lateral restraints on girders were largely unsuccessful due to their inadequate connection detail to cap beams and abutments. Reinforced concrete …

Performance Analysis Of Solar Walls In Minnesota: Final Project Report, Patrick A. Tebbe, Saeed Moaveni, Louis Schwartzkopf

Mechanical and Civil Engineering Department Publications

A study of unglazed transpired solar collectors (referred to as solar walls for this report), has been undertaken. Several installations in the Twin Cities, MN region have been identified, researched, and studied. A combination of weather stations, data logging systems, and building energy management systems were used to collect experimental data on four buildings. Performance calculations were then performed for these buildings and compared with various performance/modeling tools.

Modern Protection Systems To Prevent Corrosion Of Structural Steel Elements Due To Deicing And Roadway Salts, John J. Myers, Wei Zheng

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The effectiveness of innovative polymeric coatings, polyurea and Poly aspartic polyurea, to protect structural steel from corrosion was investigated through standard laboratory tests. the coating evaluation tests included salt fog test, QUV weathering test, adhesion test, and freeze-thaw stability test. These tests were used to assess the long-term performance of coating technologies compared to the conventional polyurethane type coatings, i.e. coating systems with inorganic zinc primer, epoxy intermediate coat and polyurethane topcoat. This paper presents part of results in the aforementioned evaluation tests. the results illustrate that Poly aspartic coating systems are very promising for corrosion mitigation and can provide …

Accelerated Construction For Pedestrian Bridges: A Comparison Between High Strength Concrete (Hsc) And High-Strength Self Consolidating Concrete (Hs-Scc), John J. Myers, Kurt Bloch

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

High-strength concrete (HSC) and glass fiber reinforced polymer (GFRP) bars are materials utilized in bridge construction to lower cost, reduce construction time, and increase service life of bridge structures. Recently, high-strength self-consolidating concrete (HS-SCC), a highly flowable concrete that does not require vibration, has been developed as a viable alternative to HSC for use in situations with congested steel or a need for rapid construction. Coupling HS-SCC with GFRP bars could create durable structures built rapidly. Several performance related issues remain to be investigated such as the behavior of prestress loss, shear, creep, shrinkage, thermal gradients, mechanical property development, time …

Implementing A Long-Term Bridge Monitoring Strategy For A Composite Steel Girder Bridge, Shelley Plude

Master's Theses

The University of Connecticut and the Connecticut Department of Transportation have established a long-term bridge health monitoring system to monitor critical vulnerabilities in a group of bridges throughout the state. This research focuses on a three-span, simply supported composite steel girder bridge carrying three lanes of highway traffic. It has been a part of the University of Connecticut and Connecticut Department of Transportation monitoring network since 2004 and is fitted with 20 strain gauges located at midspan at the top and bottom of the web of each girder.

To monitor the critical vulnerabilities of the bridge, it is important to …

Laboratory Evaluation Of Dynamic Characterization Methods For Rapid Condition Assessment Of Bridges, Jason Kyle Herrman

Graduate Theses and Dissertations

The objective of this thesis was to devise and refine Structural Health Monitoring methods and the associated quantitative characterization methods with the specific goal of enabling rapid and reliable safety evaluations of bridges following natural or manmade hazards. Presently, the safety and serviceability of these transportation infrastructure assets for use in emergency response and recovery operations are evaluated through on-site visual inspections of individual structures by teams of specially trained engineers or technicians; a process that is manpower-intensive, subjective, and slow. Specifically, the researcher was able to identify and evaluate strategies and procedures for using dynamic testing methods to rapidly …

Probabilistic Assessment Of The Friendship Trail Bridge, Rajan Sen, Gray Mullins, Niranjan Pai

Civil and Environmental Engineering Faculty Publications

The analysis performed in this study is theoretical and uses data found in the open literature rather than actual data for the bridge. The results presented indicate that the bridge is unlikely to meet a service life of an additional 20 years at reliability levels required by prevailing design codes while foregoing routine maintenance. In the light of the lower than typical reliability predicted by the analysis, more frequent bridge inspections will be needed to maintain safety in the event the bridge is repaired. vii The predictions are critically dependent on assumptions relating to the corrosion rate and statistical distributions …

Recycling Waste Latex Paint In Overlays, Rigid Pavements, And Pervious Concrete, Oscar Inez Quiroz

UNLV Theses, Dissertations, Professional Papers, and Capstones

With over 16 million gallons of latex paint (WLP) being disposed every year it is the largest by volume, liquid hazardous waste in the United States. WLP is difficult to recycle and hazardous to the environment due to the volatile organic compounds it contains. Several methods exist for disposing WLP including paint swaps, combustion, drying and discarding in a landfill, and by placing pigments in cement. Many communities are moving to dispose WLP by drying and placing in a landfill due to the reduced cost. However, this is the least preferred technique for the environment because it creates a need …

Buckling Of Profiled Steel Diaphragms, Rao V. Nunna

CCFSS Library (1939 - present)

No abstract provided.

Remote Monitoring Of Bridges, Rajan Sen, Gray Mullins, Alberto Sagues, Julio Aguilar, Danny Winters

Civil and Environmental Engineering Faculty Publications

This report summarizes findings from a 24-month study in which the performance of cathodic protection systems for substructures of two interstate bridges was remotely monitored. The two bridges #860050 and #860054 are located on the “Alligator Alley” toll portion of eastbound I-75 in Broward County, FL. Each bridge spans two pilesupported piers inside a drainage canal. The seven steel H-piles supporting the piers are jacketed in concrete to a level just below the water surface and are cathodically protected by three magnesium anodes spaced uniformly over their submerged length.

Steel Angle Section Members Under Combined Axial Load And Unsymmetric Bending, Maheshchandra Rajasekharan Phanibhushan

Civil & Environmental Engineering Theses & Dissertations

This thesis presents the outcome of an investigation into the experimental and theoretical behavior of steel angle section members under combined axial load and unsymmetric bending. Tests are conducted on a series of six angle section members provided with biaxial pinned-end boundaries about the cross-sectional non-principal axes. The end bending moments and axial load are applied in a quasi-static manner until the member load-carrying capacity is reached. The experimental load-deflection and load-strain curves are recorded. The theoretical analysis is based on a system of both elastic as well as materially nonlinear differential equations. The equations were solved using an iterative …

Flexural Behavior Of Interlocking Compressed Earth Block Shear Walls Subjected To In-Plane Loading, Bradley James Stirling

Master's Theses

This thesis investigates the flexural behavior of interlocking compressed earth block (ICEB) shear walls. In-plane cyclic tests were conducted to evaluate the performance of three flexure dominant large scale ICEB specimens: a slim wall with a 2:1 height to width aspect ratio, a flanged wall, and a wall with an opening at the center. Following the experimental investigation, two types of analyses were conducted for calculating the ultimate strength of flexure dominant ICEB walls: a nonlinear static analysis model assuming lumped plasticity and a plastic analysis model. In addition, incremental dynamic analysis was conducted to address the seismic performance of …

The Effects Of Damage Arrestment Devices In Composite Plate Sandwiches With Fastener Holes, Mark Anderson, Nancy Hung Choy, Lacey Jones, Rita Kourskaya

Aerospace Engineering

Composite materials such as a carbon fiber are used in a variety of new technologies including aircraft, spacecraft, and motor vehicles. Carbon fiber has a high strength to weight ratio, a key advantage over other material options. This report discusses the use of composite damage arrestment devices (DADs) in composite sandwich panels with a foam core. There are three different curing cycles tested for the DADs: pressure only, vacuum only, and vacuum with 1000 lbs of pressure. Using a Tetrahedron Heat Press to cure the composite specimen and an Instron Machine to perform tensile testing, data was collected for each …

Piedras Blancas Light Station Vista Point Improvement Plan, Larissa Heeren, Reuben Juster, Annamarie Usher, John Rossi, Nick Mitchell

Mechanical Engineering

Piedras Blancas Light station Improvement Involved the design of two separate parking lot/vista point plans as well as the creation of a concrete Iron Ranger located near the gift shop on site.

In-Plane Cyclic Shear Performance Of Interlocking Compressed Earth Block Walls, David William Bland

Master's Theses

This thesis presents results from testing of interlocking compressed earth block (CEB) masonry shear walls.  CEBs are low strength earth masonry units sometimes stabilized with cement or lime.  The interlocking compressed earth blocks (ICEBs) used in this experiment are dry stacked interlocking hollow units, which can be reinforced and grouted after they are laid.  Although significant research has been undertaken to optimize the material properties of CEBs, little has been done to investigate the performance of structural systems currently being built using this technology.

Test results are reported for three 1800 mm x 1800 mm wall specimens constructed with cement …

Optimization And Modeling Tools For Telescope Hexapod Structures, Michael Edward Feeney

Master's Theses

Hexapod trusses are an important element in many mechanical design systems. The natural frequency and stiffness behavior under geometric and mass variations of such structures is largely undocumented. Furthermore, the ability to quickly model hexapod designs and explore a large design-space in finite element software packages is, in general, time consuming and inefficient. The purpose of this project was to develop software tools that made design-space exploration (modeling and simulation processes) for hexapod structures drastically more efficient. Secondly, the project included an experimental analysis portion to demonstrate the various modal study techniques and to validate finite element analysis predictions. Lastly, …

Rate-Dependent Behavior Of Clay, Harry F. Martindale Iv

Master's Theses

This thesis presents a strain-rate dependent two-surface plasticity constitutive model for clays based on the critical-state soil mechanics.  The model reproduces the mechanical response of clays under multi-axial loading conditions and predicts both drained and undrained behaviors at small and large strains.  Model parameter values are determined for Boston Blue Clay, London Clay and Kaolin Clay.  The performance of the model in simulating the mechanical response of clays is demonstrated for a variety of strain rates. Sensitivity of each model parameter is checked for ±5, ±10 and ±20% of the deterministic values. Probabilistic analysis using Monte Carlo simulations were done …

Residual Strength Of Ultra-High Performance Concrete After Exposure To Elevated Temperatures, Brian T. Burke

Master's Theses

This paper presents the results of a study on the effect of elevated temperatures on the compressive strength of ultra-high-performance fiber-reinforced concrete (UHPFRC). Two different mixtures of a commercially available UHPFRC were considered in this study. The standard mixture offered by the manufacturer incorporates only steel-fibers to improve the tensile properties of the concrete. The enhanced mixture, which is of primary focus in the study, incorporates additional polypropylene fibers to improve the fire-resistance behavior. Specimens from each mixture were cast into 76 mm (3 in.) diameter cylinders and 51 mm (2 in.) cubes. After exposure to elevated temperatures …

Two Dimensional Modeling Of Wind Effects On A Bridge Section Using Finite Difference Method, Jessica Carreiro

Civil Engineering Undergraduate Honors Theses

Wind effects on long span bridges are a major concern for bridge design. Wind acts as a dynamic load on the bridge deck causing the bridge to react in ways not accounted for in static load design. Attention to these effects increased tremendously after famous bridge collapses, such as the Tacoma Narrows Bridge in 1940. Due to this collapse and others, engineers were made painfully aware that wind phenomena, such as flutter and vortex shedding, can cause major structural damage if not considered in the design process. The solution for many years since has been to conduct wind tunnel tests …

Enhancing Progressive Collapse Resistance Of Steel Building Frames Using Thin Infill Steel Panels, Victor M. Sanchez Escalera

Master's Theses

Progressive collapse occurs when damage from a localized first failure spreads in a domino effect manner resulting in a total damage disproportionate to the initial failure.  Recent building failures (e.g., World Trade Center twin towers) highlight the catastrophic outcome of progressive collapse.  This research proposes a reliable and realistic retrofit technology which installs thin steel panels into steel building structural frames to enhance the system progressive collapse resistance.

The steel frames with simple beam-to-column connections, under different boundary conditions (i.e., sidesway uninhibited and sidesway inhibited, respectively), and the loss of one bottom story column were retrofitted using the proposed technology …