Structural Engineering Commons^™

The Effect Of Lane Changing On Long-Span Highway Bridge Traffic Loading, Bernard Enright, Colm Carey, Colin C. Caprani

Conference papers

Maximum loading on long-span bridges typically occurs in congested traffic conditions. As traffic becomes congested car drivers may change lane, increasing the tendency for trucks to travel in platoons. For long-span bridges this phenomenon may increase the regularity and severity of bridge repair programs, with potential significant associated costs. This research investigates the effect of lane changing by car drivers on bridge loading. A Monte Carlo simulation model in which individual car drivers probabilistically decide, based on a lane-changing bias probability, whether or not to change lane has been developed. The sensitivity of bridge loading to this factor is investigated …

Estimating Characteristic Bridge Loads On A Non-Primary Road Network, Eugene J. Obrien, Bernard Enright, Brendan Williams, Cathal Leahy

Conference papers

When collecting truck loading data on a primary road network a common approach is to install a large network of permanent pavement-based Weigh-In-Motion systems. An alternative to this approach would be to use one or more portable Bridge Weigh-In-Motion systems which could be moved between bridges at regular intervals to determine the traffic loading throughout the network. A data collection strategy is needed to put such a system to best use. This paper details the data collection strategies which were examined for the National Roads Authority in Ireland. The use of urban economic concepts including Central Place Theory are discussed …

Reliability Analysis Of Footbridge Serviceability Considering Crowd Loading, Joe Keogh, Colin C. Caprani, Paul Archbold, Paul Fanning

Conference papers

The characteristic vertical response of flexible footbridges subjected to single pedestrian and crowd loading is examined in this paper. Typically, bridge vibrations produced from a crowd of pedestrians are estimated by using an enhancement factor applied to the effect caused by a single pedestrian. In this paper a moving force model is used in Monte Carlo simulations of a non-homogeneous sample of single pedestrians and crowds to estimate characteristic vertical vibration levels. Also in this work, statistical distributions of the bridge parameters are considered, these include flexural rigidity, mass and rotational stiffness at the supports. It was previously proven by …

The Effect Of Clusters Within Crowds Of Pedestrians On The Vertical Response Of A Flexible Footbridge, Joe Keogh, Colin C. Caprani, Paul Archbold, Paul Fanning

Conference papers

The issue of excessive vibrations of footbridges due to the passage of pedestrians has been well documented in the past decade. Despite this there still remains great uncertainty as to how to predict the acceleration response of a footbridge due to crowd loading. This paper investigates the vibration response of a flexible footbridge subjected to crowd loading. Using a statistical model which caters for the variability of pedestrians, the vibration response of the footbridge is obtained. In this work, the effect of social groups or clusters of pedestrians in a crowd is investigated. Herein a cluster is defined as two …

Probabilistic Study Of Lifetime Load Effect Distribution Of Bridges, Donya Hajializadeh, Eugene J. Obrien, Bernard Enright, Colin C. Caprani, Emma Sheils, Simon Wilson

Conference papers

Assessment of highway bridge safety requires a prediction of the probability of occurrence of extreme load effects during the remaining life of the structure. While the assessment of the strength of an existing bridge is relatively well understood, the traffic loading it is subject to, has received less attention in the literature. The recorded traffic data are often limited to a number of days or weeks due to the cost of data collection. Studies in the literature have used many different methods to predict the lifetime maximum bridge load effect using a small amount of data, including fitting block maximum …

Resilience Of Bridges Following Aftershocks, Diego Francisco Espinosa

Electronic Theses and Dissertations

The ability to predict the reduction in capacity of a structure after an earthquake is vital in the process of assessing a structure after a main-shock or an after-shock. Main-shocks are normally followed by a few aftershocks in a short period of time. Researchers in the past have focused for the most part on the effects of main-shocks on buildings. Very little research has been performed on the ability to predict the reduction in capacity of bridges in aftershocks. This thesis focuses on providing a way of assessing the reduction in capacity for main-shocks as compared to aftershocks and the …

Performance Of Mechanical And Non-Mechanical Connections To Gfrp Components, Nnadozie N. Dike

Electronic Theses and Dissertations

There are presently many solutions to dealing with aging or deteriorated structures. Depending on the state of the structure, it may need to be completely over-hauled, demolished and replaced, or only specific components may need rehabilitation. In the case of bridges, rehabilitation and maintenance of the decks are critical needs for infrastructure management. Viable rehabilitation options include replacement of decks with aluminum extrusions, hybrid composite and sandwich systems, precast reinforced concrete systems, or the use of pultruded fiber-reinforced polymer (FRP) shapes. Previous research using pultruded glass fiber-reinforced polymer (GFRP) decks, focused on behaviour under various strength and serviceability loading conditions. …

Monte Carlo Simulation Of Extreme Traffic Loading On Short And Medium Span Bridges, Bernard Enright, Eugene J. Obrien

Articles

The accurate estimation of site-specific lifetime extreme traffic load effects is an important element in the cost-effective assessment of bridges. A common approach is to use statistical distributions derived from weigh-in-motion measurements as the basis for Monte Carlo simulation of traffic loading. However, results are highly sensitive to the assumptions made, not just with regard to vehicle weights but also to axle configurations and gaps between vehicles. This paper presents a comprehensive model for Monte Carlo simulation of bridge loading for free-flowing traffic, and shows how the model matches results from measurements on five European highways. The model has been …

An Empirical Study Of Particulate Matter Exposure For Transit Users At Bus Stop Shelters, Adam Moore

Dissertations and Theses

Congested traffic corridors in dense urban areas are key contributors to the degradation of urban air quality. While waiting at bus stops, transit patrons may be exposed to greater amounts of vehicle-based pollution, including particulate matter, due to their proximity to the roadway. Current guidelines for the location and design of bus stops do not take into account air quality or exposure considerations. This thesis provides a unique contribution to roadside air quality studies and presents an innovative method for the consideration of bus shelter placement. Exposure to roadside pollutants is estimated for transit riders waiting at three-sided bus stop …

A Study Of Creep And Shrinkage In Concrete With A Consideration Of Its Effects On Curved Post-Tensioned Concrete Bridges, William O'Sullivan

Theses

The first objective of the project was to explore the differences between Ordinary Portland Cement (OPC) and Ground Granulated Blast-Furnace Slag (GGBS) cement. The use of GGBS cement concrete is increasing in industry due to the environmental and durability benefits it gives compared with OPC concrete. Data on the creep properties of GGBS cement concrete is limited compared with the data that is available for OPC concrete. Laboratory testing was undertaken to determine the different effects of creep on OPC concrete and GGBS concrete.

The second project objective was to research the effects of creep on post - tensioned curved …

The Response Of A Footbridge To Pedestrians Carrying Additional Mass, Darragh O'Sullivan, Colin Caprani, Joe Keogh

Conference papers

Footbridges with low natural frequency are susceptible to excessive vibration serviceability problems if the pedestrian pacing frequency matches the bridge natural frequency. Much research has been done into describing the response of a footbridge to single pedestrian loading. However, many pedestrians carry additional mass such as shopping bags and backpacks, and this has generally not been accounted for in previous research. This work examines this problem using an experimental bridge excited with many single pedestrian events, both with and without additional mass. The vertical acceleration response is measured and compared to moving force, moving mass, and moving spring-mass-damper models. The …

Lane Changing Control To Reduce Traffic Load Effect On Long-Span Bridges, Colin C. Caprani, Bernard Enright, Colm Carey

Conference papers

Long span bridges are critical parts of a nation’s infrastructure network and congested traffic loading is the governing form of traffic loading. Groups of trucks travelling in conveys are created when fast-er moving vehicles, such as cars, change lane. In this research the authors investigate how the control of these lane-changing events can help reduce the traffic load effects on long span bridges. Real traffic data is used to simulate a traffic stream on a virtual road and bridge using a microsimulation model. Various lane-changing restrictions are examined and compared to the typical case of free lane changing. It is …

Estimation Of Lifetime Maximum Distributions Of Bridge Traffic Load Effects, Eugene J. Obrien, Donya Hajializadeh, Emma Sheils, Bernard Enright

Conference papers

This paper considers the problem of assessing traffic loading on road bridges. A database of European WIM data is used to determine accurate annual maximum distributions of load effect. These in turn are used to find the probability of failure for a number of load effects. Using the probability of failure as the benchmark, traditional measures of safety – factor of safety and reliability index – are reviewed. Both are found to give inconsistent results, i.e., a given factor of safety or reliability index actually corresponds to a range of different probabilities of failure.

Effects Of Cyclic Loading On Offshore Foundation Systems, Shane Browne

Theses

A brief description of the various offshore foundation systems currently available is provided in this report, including the advantages and disadvantages for each system and water depth in which they can be used. These foundation types include floating structures, jacket structures, gravity base structures and the monopile foundation, on which this research specifically focuses.

The monotonic lateral loading of the monopile structure is also examined and the reasons why monotonic testing is required are highlighted, along with the potential analysis that can be generated to improve the design of the monopile foundation. A review of previous test programmes for monopiles …

Optimisation Of Cold-Formed Steel Purlin Cross-Sections, Matt Clifford

Theses

The subject of buckling of steel members is introduced and the critical nature of local buckling in slender members is highlighted.

The main thrust of work this semester is an investigation into the following buckling modes:

Flexural buckling;

Lateral torsional buckling;

Torsional buckling;

Shear buckling;

Web buckling;

Distortional buckling;

Local buckling.

This investigation has three main components:

1. Review of theory, books and appropriate published work;

2. Investigation into the relevant parts of Eurocode 3;

3. Finite element analysis using the LUSAS FE program to illustrate the various buckling modes.

Finally, the areas to be covered in the Realisation Stage …

Failure Analysis Of Impact-Damaged Metallic Poles Repaired With Fiber Reinforced Polymer Composites, Robert Arthur Slade

Electronic Theses and Dissertations

Metallic utility poles, light poles, and mast arms are intermittently damaged by vehicle collision. In many cases the vehicular impact does not cause immediate failure of the structure, but induces localized damage that may result in failure under extreme service loadings or can promote degradation and corrosion within the damaged region. Replacement of these poles is costly and often involves prolonged lane closures, service interruption, and temporary loss of functionality. Therefore, an in situ repair of these structures is required. This thesis examines the failure modes of damaged metallic poles reinforced with externally-bonded fiber reinforced polymer (FRP) composites. Several FRP …

The Structural Performance Of Timber Connections, Daniel Coleman

Theses

This thesis sets out to assess the behaviour of mechanically fastened timber-to-timber connections. The design aspects of timber connections are described in detail, with particular emphasis on nailed connections. The effects of inherent variations in timber properties on joint behaviour are also described.

The two types of connections considered were:

■ Corbel (cantilever);

■ Splice.

For each connection type, different nail configurations, nail diameters and shaft lengths were used. Testing undertaken was conducted to investigate the influence of a number of nail configurations on a connection’s initial stiffness. The test results, presented using moment- rotation curves are also used to …

Vertical Response Of A Footbridge Subjected To Stocastic Crowd Loading, Joe Keogh

Conference papers

No abstract provided.

Portable Bridge Wim Data Collection Strategy For Secondary Roads, Bernard Enright, Cathal Leahy, Eugene J. Obrien, Jennifer Keenahan

Conference papers

A common method of collecting traffic loading data across a large road network is to use a network of permanent pavement-based WIM systems. An alternative is to use one or more portable Bridge Weigh-In-Motion systems which are moved periodically between bridges on the network. To make optimum use of such a system, a suitable data collection strategy is needed to choose locations for the system. This paper describes a number of possible strategies which the authors have investigated for the National Roads Authority in Ireland. The different strategies are examined and their advantages and disadvantages compared. Their effectiveness at detecting …

Structural Topology Optimization: Moving Beyond Linear Elastic Design Objectives, James K. Guest, Reza Lotfi, Andrew T. Gaynor, Mehdi Jalalpour

Civil and Environmental Engineering Faculty Publications

Topology optimization is a systematic, free-form approach to the design of structures. It simultaneously optimizes material quantities and system connectivity, enabling the discovery of new, high-performance structural concepts. While powerful, this design freedom has a tendency to produce solutions that are unrealizable or impractical from a structural engineering perspective. Examples include overly complex topologies that are expensive to construct and ultra-slender subsystems that may be overly susceptible to imperfections. This paper summarizes recent tools developed by the authors capable of mitigating these shortcomings through consideration of (1) constructability, (2) nonlinear mechanics, and (3) uncertainties.

Interfacing Building Response With Human Behavior Under Seismic Events, Z. Liu, Mehdi Jalalpour, C. Jacques, S. Szyniszewski, J. Mitrani-Reiser, James K. Guest, T. Igusa, B. W. Schafer

Civil and Environmental Engineering Faculty Publications

The goal of this paper is to model the interaction of humans with their built environment during and immediately following a natural disaster. The study uses finite element simulations to evaluate the response of buildings under input ground motions and agent-based dynamic modeling to model the subsequent evacuation of building occupants in the study area immediately following the seismic event. The structural model directly captures building damage and collapse, as well as floor accelerations and displacements to determine nonstructural damage, injuries and fatalities. The goal of this research is to make connections between building damage and occupant injuries, with geographic …

Flexural Behavior Of Laterally Damaged Full-Scale Bridge Girders Through The Use Of Carbon Fiber Reinforced Polymers (Cfrp), Nicholas James Alteri

UNF Graduate Theses and Dissertations

ABSTRACT

The repair and strengthening of concrete bridge members with CFRP has become increasingly popular over recent years. However, significant research is still needed in order to develop more robust guidelines and specifications. The research project aims to assist with improving design procedures for damaged concrete members with the use of CFRP.

This document summarizes the analysis and testing of full-scale 40’ foot long prestressed concrete (PSC) bridge girders exposed to simulated impact damage and repaired with carbon fiber reinforced polymers (CFRP) materials. A total of five AASHTO type II bridge girders fabricated in the 1960’s were taken from an …

Developments In Performance Monitoring Of Concrete Exposed To Extreme Environments., W. J. Mccarter, T. M. Chrisp, G. Starrs, A. Adamson, E. Owens, P. A. M. Basheer, S. V. Nanukuttan, S. Srinivasan, Niall Holmes

Articles

The performance of the surface zone of concrete is acknowledged as a major factor governing the rate of deterioration of reinforced concrete structures because it provides the only barrier to the ingress of water containing dissolved ionic species such as chlorides, which ultimately initiate corrosion of the reinforcement. In situ monitoring of cover-zone concrete is therefore critical in attempting to make realistic predictions as to the in-service performance of the structure. To this end, this paper presents developments in a remote interrogation system to allow for continuous, real-time monitoring of the cover-zone concrete from an office setting. Use is made …

Development Of Self-Stressing System For Bridge Application With Emphasis On Precast Panel Deck System, Marcelo Ferreira Da Silva

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

Steel girder bridges often utilize continuity over the pier to reduce interior forces on the spans. In continuous structures with composite concrete decks, the location of maximum negative bending moment is over the interior supports. This moment produces tensile stresses in the concrete deck and compressive stress in the bottom flanges of the girders. The tensile stress in the deck leads to cracking which allow intrusion of moisture and road salt, causing corrosion of the reinforcement and supporting girders. Continued maintenance is required to forestall the deterioration; however, replacement of the deck is eventually required.

To overcome this problem, a …

Expanding The Length Of Jointless Bridges By Providing Rotational Capacity Over The Pile Head, Ardalan Sherafati

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

Jointless bridges have been in service for more than 50 years. Since no expansion joint is utilized in these structures, they have longer service life, reduced maintenance and construction costs, improved riding quality, and added redundancy. Because of integrity of the superstructure with the substructure, the thermal movements as well as other longitudinal movements are transferred to substructure. These lateral movements can induce relatively large forces and moments in the substructure elements including the abutment and the piles. Typically, flexible foundations which include single row of piles are preferred in jointless bridges to reduce the stiffness of the system against …

Development Of A Design Procedure For Concrete Traffic Barrier Attachments To Bridge Decks Utilizing Epoxy Concrete Anchors, Benjamin J. Dickey

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

A guide for the design of epoxy anchors for the use in concrete traffic barriers was developed in this study. A series of dynamic bogie tests and static tests was conducted on single and double anchors. The dynamic increase factor for the noted anchors was determined to be 1.06. Protective epoxy coatings for the anchors was observed to contribute to a 9 percent decrease in anchorage strength. The effects of anchors located in close proximity to each other was also investigated. Calibration factors were developed to apply recommended changes to the ACI code for use in bridge rail anchorages.

A …

Wim Based Load Models For Bridge Serviceability Limit States, Przemyslaw Rakoczy

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

The safety of aging bridge inventory is one of the main concerns of the state and federal agencies. Therefore, there is a need to quantify the safety margin of existing infrastructure and new design bridges. The Serviceability Limit States, i.e. fatigue, requires additional statistical parameters and not only the maximum values but also load spectra, i.e. frequency of occurrence of loads. The maximum values are needed for shorter time periods, such as day, week, month or year. Load spectra as well as material resistance are random variables. To quantify the safety margin of existing and future bridges load and resistance …

Effect Of Copper Addition On Mechanical Properties And Electrical Conductivity Of Pp/C-Cu Bipolar Plate Composites, Anne Zulfia, Taufik Abimanyu, Verina Warga Dalam

Makara Journal of Technology

Effect of Copper Addition on Mechanical Properties and Electrical Conductivity of PP/C-Cu Bipolar Plate Composites. Bipolar plate is a major component in PEM fuel cell which possess main function of collecting and removing electrons from anode to cathode. Therefore, materials for bipolar plates produced must have high electrical conductivity. To obtain bipolar plate materials which is cheap, lightweight and high conductivity, so it is developed bipolar plates material based on PP/C-Cu composite. PP/C-Cu composites has been made by mixing all materials then compounding, rheomix, hot blending and hot press. Cu (Copper) has been used various from 0.1 wt%, 1 wt% …

Application Of Empirical Orthogonal Function Models To Analyze Shoreline Change At Bangkalan Madura, Darius Arkwright, Suntoyo Suntoyo

Makara Journal of Technology

Bangkalan’s shoreline, especially on the opposite side of Surabaya, has been evaluated to determine the morphological changes due to wave attack, near-shore current, long-shore sediment transport and coastal configuration. This research aims to determine the dominant patterns of variation of Bangkalan’s shoreline change, expressed by Eigen-function in empirical orthogonal function (EOF) models. That was started with data collection such as oceanographic data (wave and tidal), bathymetry and topographic map and sediment data. All data was used for forecasting two-monthly shoreline. Coordinate of two-monthly shoreline was used as input of EOF model. The first Eigen mode is a profile of shoreline …

The Effectiveness Of Anaerobic Baffled Reactor And Rotating Biological Contactor In Batik Wastewater Treatment, Augustinus Ignatius Kristijanto, Widhi Handayani, Purwanti Asih Anna Levi

Makara Journal of Technology

Batik is one of popular arts of Indonesia. The batik industries in Sragen, Central Java, are prepared to compete in global market. In order to realize that objective, batik products should fulfill some qualifications, one of which is “environmental friendliness”. As batik production is usually generating wastewater which pollutes the environment, the technology of wastewater treatment should be developed to solve the problem. This preliminary study has been done to assess the effectiveness of anaerobic baffled reactor (ABR) and rotating biological contactor (RBC) in batik wastewater treatment. In 40 days of treatment period, the ABR performance in reducing pollutants showed …