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Full-Text Articles in Engineering

The Probabilistic Characterization Of Severe Rainstorm Events: Applications Of Threshold Analysis To Climate Change Impacts, Barry A. Palynchuk Phd Dec 2013

The Probabilistic Characterization Of Severe Rainstorm Events: Applications Of Threshold Analysis To Climate Change Impacts, Barry A. Palynchuk Phd

Barry A. Palynchuk PhD

A summary of PhD thesis, with emphasis upon storm event definition, and climate change impacts upon rainfall depth, duration, and intensity.


Bridge-Track Interaction Under Elevated Temperatures, Sakdirat Kaewunruen Dec 2013

Bridge-Track Interaction Under Elevated Temperatures, Sakdirat Kaewunruen

Sakdirat Kaewunruen

This paper presents the adaptability to short-term climate variability and extreme events of existing infrastructures in Australia, especially railway track bridges. The main objective of this research was to analyse the interaction between the track and bridge under elevated temperatures. The scope of work was to evaluate the behaviour of the track and bridge interaction throughout temperature ranges experienced in summer periods whereas the expansion and contraction of materials are different in nature. This investigation was emphasised on the differential longitudinal behaviours of railway track and bridge structure. A nonlinear 3D finite element model of a railway bridge (ballast top) …


Investigation Of Crashes And Identifying The Best Practices For Setting Up Speed Zones In Towns Along Rural Highways In Nevada, Krishna Prasad Shrestha Nov 2013

Investigation Of Crashes And Identifying The Best Practices For Setting Up Speed Zones In Towns Along Rural Highways In Nevada, Krishna Prasad Shrestha

Joseph Shrestha

In 2010, 51,664 crashes occurred in Nevada. Only about 9% of those crashes occurred in rural areas of the state. However, if only fatal crashes are considered, 41% of those fatal crashes occurred in rural areas. Generally, speed zones are provided in towns along rural highways to reduce speed-related crashes. However, a guideline is necessary for a consistent procedure to setup speed zones throughout the state. The main objectives of this study are to determine factors associated with crashes and to identify the best practices for setting up speed zones in towns along rural highways.

Eleven towns along rural highways …


Improving Efficiency Of Indot Traffic Data Collection Using Gps Devices, Shuo Li, Karen Zhu, Boudewijn H. W. Van Gelder, John Nagle, Carl Tuttle Nov 2013

Improving Efficiency Of Indot Traffic Data Collection Using Gps Devices, Shuo Li, Karen Zhu, Boudewijn H. W. Van Gelder, John Nagle, Carl Tuttle

John Copeland Nagle

INDOT has utilized many new technologies to reduce travel delay, mitigate traffic congestion, and enhance public and employees’ safety. Many projects are underway, including re-timing of most existing traffic signals and pavement maintenance and rehabilitation. To evaluate signal system performance, prioritize alternatives of improvement, conduct before and after studies and investigate work zone safety, it requires a large amount of traffic data such as travel time, speed and delay. Issues, such as safety, efficiency and cost, may arise associated with the current methods. For the current manual or automatic data collection, it usually requires two operators, a driver and a …


Determination Of Practical Esals Per Truck Values On Indiana Roads, Sedat Gulen, John Nagle, John Weaver, Victor Lee Gallivan Nov 2013

Determination Of Practical Esals Per Truck Values On Indiana Roads, Sedat Gulen, John Nagle, John Weaver, Victor Lee Gallivan

John Copeland Nagle

The Indiana Department of Transportation (INDOT) has been using ESAL (Equivalent Single Axle Load) values for pavement design. The current ESAL values were obtained in the late 1970. However, truck deregulation and higher allowable maximum loads have increased the 1970's values. Updated ESAL values are needed for better road designs. The 1998 and 1999 traffic data from the all Weight-in-Motion (WIM) stations were obtained and used to compute updated ESAL values for multiple unit trucks (Class 9/F-9) and single unit trucks (Class 5, 6 and 7). Statistical analyses indicated that average ESAL values for 1998 and 1999 are statistically the …


Decorative Ferrocement Elements, Letitia Nadasan, Traian Onet, Ana Ioana Petean, Marian Sabau Oct 2013

Decorative Ferrocement Elements, Letitia Nadasan, Traian Onet, Ana Ioana Petean, Marian Sabau

Marian Sabau

Ferrocement has the versatility that can be 'sculptured' or shaped into numerous fascinating structures and objects for very wide applications. The exposure of this technology to engineers in general is rather minimal in Romania and many are skeptical about it. The potential is not exploited for it being unconventional in nature. Its ability to compete or use as a cheaper alternative and yet a promising technology in ensuring improved living standard and environmental quality must not be neglected. The paper discusses about the applicability of ferrocement in the Romanian scene with respect to recreation and home use. The ferrocement elements …


Project Complexity Mapping In Five Dimensions For Complex Transportation Projects, Douglas D. Gransberg, Jennifer S. Shane, Carla Lopez Del Puerto Oct 2013

Project Complexity Mapping In Five Dimensions For Complex Transportation Projects, Douglas D. Gransberg, Jennifer S. Shane, Carla Lopez Del Puerto

Douglas D. Gransberg

Traditional three-dimensional project management theory is based on optimizing the cost-schedule-technical dimensions. Recent studies in the United Kingdom, Canada, and Australia have shown that the current project management body of knowledge may not be adequate to address interrelated and dependent variables encountered on complex projects. This paper reports the findings of an international research team’s detailed study of eighteen complex projects, which confirms the findings of the previous research and proposes a framework upon which a complex transportation project’s scope of work can be better conceptualized and a methodology to graphically display a project’s complexity in order to better understand …


Drop Weight Testing On Sandwich Panels With A Novel Thermoplastic Core Material, Christopher Y. Tuan Sep 2013

Drop Weight Testing On Sandwich Panels With A Novel Thermoplastic Core Material, Christopher Y. Tuan

Christopher Y. Tuan

A series of drop weight tests were conducted to evaluate the dynamic flatwise compression strength and flexural strength of sandwich panels with a novel core structure. This sandwich core material, known as Norcore, consists of interconnected cells in a unique configuration of truncated pyramid with sloping cell walls. Core materials made of thermoplastic including virgin Lexan, polycarbonate, polycarbonate regrind, high-impact polystyrene, and acrylonitrile butadiene styrene were tested. The test results showed that these sandwich panels have good strength as well as energy absorption capacities.


Acoustic And Dynamic Characteristics Of A Complex Urban Turnout Using Fibre-Reinforced Foamed Urethane (Ffu) Bearers, Sakdirat Kaewunruen Sep 2013

Acoustic And Dynamic Characteristics Of A Complex Urban Turnout Using Fibre-Reinforced Foamed Urethane (Ffu) Bearers, Sakdirat Kaewunruen

Sakdirat Kaewunruen

A special track system used to divert a train to other directions or other tracks is generally called ‘railway turnout’. A traditional turnout system includes rails, switches, crossings (special track components), steel plates, fasteners, screw spikes, timber bearers, ballast and formation. The wheel rail contact over the crossing transfer zone has a dip-like shape and can often cause detrimental impact loads on the railway track and its components. The large impact also emits disturbing noises (either impact or ground-borne noise) to railway neighbors. In a brown-field railway track where an existing aged infrastructure requires renewal or maintenance, some physical constraints …


Efectul Confinării Asupra Conlucrării Betonului Autocompactant Cu Armătura, Marian Sabau Aug 2013

Efectul Confinării Asupra Conlucrării Betonului Autocompactant Cu Armătura, Marian Sabau

Marian Sabau

Prezenta lucrare aduce contribuții legate de fenomenul de aderenţă dintre betonul autocompactant şi armătură. Principalul obiectiv al programului experimental a fost studierea fenomenului de aderenţă dintre betonul autocompactant şi barele de armătură, mai precis a efectului confinării betonului cu armătură transversală, pentru validarea sau îmbunătăţirea modelelor teoretice existente.


Engineering Properties Of Oil Palm Shell Lightweight Concrete Containing Fly Ash, Hilmi Mahmud Aug 2013

Engineering Properties Of Oil Palm Shell Lightweight Concrete Containing Fly Ash, Hilmi Mahmud

Hilmi Mahmud

The effect of cement replacement with type F fly ash at 0%, 10%, 30% and 50% on some engineering properties of an oil palm shell (OPS) high strength lightweight concrete was investigated. The properties studied include workability, density, compressive strength, splitting tensile strength, flexural strength, water absorption and drying shrinkage. The effect of initial water curing periods of 2, 4 and 6. days after demoulding and air drying environment on the 28-day compressive strength was also investigated. The test results showed that even with 50% substitution of cement with fly ash, a low cost grade 30 OPS lightweight concrete can …


Experimental Determination On Bond Strength Of Rebar In Self-Compacting Concrete, Marian Sabau, Traian Onet, Ana Ioana Petean Jun 2013

Experimental Determination On Bond Strength Of Rebar In Self-Compacting Concrete, Marian Sabau, Traian Onet, Ana Ioana Petean

Marian Sabau

Experimental results of the local bond stress-slip relationship of deformed reinforcing bars embedded in confined self-compacting concrete are presented. A total of 58 pull-out specimens were tested. Each one of these specimens simulated the confined region of a beam-column joint. The main analyzed parameters were the concrete type, the confining reinforcement, the reinforcement bar diameter, the embedded length of bars. The results showed that in order to ensure that the bond failure is caused by pull-out, a restraining reinforcement must be provided. The paper also presents a comparison between self-compacting concrete (SCC) and normally vibrated concrete (NVC).


Investigation Of Bio-Hydrogen And Bio-Methane Production From Thin Stillage, Noha El-Sayed Nasr May 2013

Investigation Of Bio-Hydrogen And Bio-Methane Production From Thin Stillage, Noha El-Sayed Nasr

Noha El-Sayed Nasr

An evaluation of single-stage and two-stage anaerobic digestion processes for biomethane and biohydrogen production using thin stillage was performed to assess the viability of biohydrogen production from thin stillage and the impact of separating the acidogenic and methanogenic stages on anaerobic digestion with hydrogen production in the first stage. A comparative evaluation of anaerobic digester sludge (ADS) and acclimatized anaerobic digester sludge (AADS) for biohydrogen production was performed at various S°/X° ratios. The optimum range of S°/X° ratio for hydrogen production was found to be 1 to 2 gCOD/gVSS using conventional ADS and 3 to 6 gCOD/gVSS using AADS. Maximum …


Climate Change Adaptation Chapter: Marshfield, Massachusetts, Joshua H. Chase, Jonathan G. Cooper, Rory Elizabeth Fitzgerald, Filipe Antunes Lima, Sally R. Miller, Toni Marie Pignatelli May 2013

Climate Change Adaptation Chapter: Marshfield, Massachusetts, Joshua H. Chase, Jonathan G. Cooper, Rory Elizabeth Fitzgerald, Filipe Antunes Lima, Sally R. Miller, Toni Marie Pignatelli

Jonathan G. Cooper

Climate change, understood as a statistically significant variation in the mean state of the climate or its variability, is the greatest environmental challenge of this generation (Intergovernmental Panel on Climate Change, 2001). Marshfield is already being affected by changes in the climate that will have a profound effect on the town’s economy, public health, coastal resources, natural features, water systems, and public and private infrastructure. Adaptation strategies have been widely recognized as playing an important role in improving a community’s ability to respond to climate stressors by resisting damage and recovering quickly. Based on review of climate projections for the …


Economia De Energie Realizată Prin Folosirea Betonului Autocompactant, Marian Sabau, Traian Onet, Ana Ioana Petean, Letitia Nadasan May 2013

Economia De Energie Realizată Prin Folosirea Betonului Autocompactant, Marian Sabau, Traian Onet, Ana Ioana Petean, Letitia Nadasan

Marian Sabau

Betonul autocompactant (BAC) este un beton inovativ care nu necesită vibrare în momentul punerii în operă, acesta fiind capabil să curgă sub propia greutate, poate să umple complet cofrajele şi să ajungă la o compactare corespunzătoare fără a fi nevoie de o compactare mecanică. Această lucrare prezintă avantajele acestui nou tip de beton, materialele constituente, metodele de testare, precum şi dezavantajele care le aduce compactarea prin vibrare asupra betonului obişnuit. Eliminarea vibrării are de asemenea efecte benefice asupra condițiilor de muncă în procesul de producere al betonului.


Safety Impacts Of Signal-Warning Flashers And Speed Control At High-Speed Signalized Intersections, Zifeng Wu, Anuj Sharma, Fred L. Mannering, Shefang Wang May 2013

Safety Impacts Of Signal-Warning Flashers And Speed Control At High-Speed Signalized Intersections, Zifeng Wu, Anuj Sharma, Fred L. Mannering, Shefang Wang

Anuj Sharma

For many years, to reduce the crash frequency and severity at high-speed signalized intersections, warning flashers have been used to alert drivers of potential traffic-signal changes. Recently, more aggressive countermeasures at such intersections include a speed-limit reduction in addition to warning flashers. While such speed-control strategies have the potential to further improve the crash-mitigation effectiveness of warning flashers, a rigorous statistical analysis of crash data from such intersections has not been undertaken to date. This paper uses 10-year crash data from 28 intersections in Nebraska (all with intersection approaches having signal-warning flashers; some with no speed-limit reduction, and the others …


Recasting Dilemma Zone Design As A Marginal Cost-Benefit Problem, Anuj Sharma, Darcy M. Bullock, Srinivas Peeta Apr 2013

Recasting Dilemma Zone Design As A Marginal Cost-Benefit Problem, Anuj Sharma, Darcy M. Bullock, Srinivas Peeta

Anuj Sharma

One control objective at high-speed isolated intersections is to provide safe phase transition by minimizing the occurrence of high-speed vehicles in the dilemma zone before the phase is terminated. An upper limit for extending the green (maximum green time) is used to avoid an indefinite extension of the main-street green. Currently, the maximum green times are chosen by using engineering judgment. This approach does not explicitly consider the trade-offs between safety and delay and hence often results in both unsafe and inefficient performance at the intersection under medium to heavy traffic volumes. The dilemma problem is recast as one of …


Effect Of Phase Countdown Timers On Queue Discharge Characteristics Under Heterogeneous Traffic Conditions, Anuj Sharma Apr 2013

Effect Of Phase Countdown Timers On Queue Discharge Characteristics Under Heterogeneous Traffic Conditions, Anuj Sharma

Anuj Sharma

Analysis of queue discharge characteristics at signalized intersections is a primary component of traffic signal analysis and design. On the basis of previous studies, mainly conducted in homogeneous traffic conditions, the discharge headway is assumed to be high at the start of green for the first few vehicles, mainly because of start-up lost times, and is also assumed to reach the minimum value by the fourth or fifth vehicle in the queue. The minimum headway is expected to continue until the end of the queue. However, this may not be the case under heterogeneous traffic conditions, such as those in …


Determination Of Traffic Responsive Plan Selection Factors And Thresholds Using Artificial Neural Networks, Anuj Sharma Apr 2013

Determination Of Traffic Responsive Plan Selection Factors And Thresholds Using Artificial Neural Networks, Anuj Sharma

Anuj Sharma

Traffic congestion has become a menace to civilized society. It degrades air quality, jeopardizes safety and causes delay. Traffic congestion can be alleviated by providing an effective traffic control signal system. Closed-loop traffic control systems are an example of such a system. Closed-loop traffic control systems can be operated primarily in either of two modes: Time of Day Mode (TOD) or Traffic Responsive Plan Selection Mode (TRPS). TRPS mode, if properly configured, can easily handle time independent variation in traffic volumes. It can also reduce the effect of timing plan aging. Despite these advantages, TRPS mode is not used as …


Event-Based Data Collection For Generating Actuated Controller Performance Measures, Edward J. Smaglik, Anuj Sharma, Darcy M. Bullock, James R. Sturdevant, Gary Duncan Apr 2013

Event-Based Data Collection For Generating Actuated Controller Performance Measures, Edward J. Smaglik, Anuj Sharma, Darcy M. Bullock, James R. Sturdevant, Gary Duncan

Anuj Sharma

Cycle-by-cycle data have been shown to be effective in the analysis of a signalized intersection with measures of effectiveness such as volume-to-capacity ratios, arrival type, and average vehicular delay. Currently, actuated traffic controllers are unable to store vehicle counts and vehicle occupancy in cycle-by-cycle bins, requiring extra equipment and personnel to collect data in these bins. The objective of this research was to develop an integrated general purpose data collection module that time stamps detector and phase state changes within a National Electrical Manufacturers Association actuated traffic signal controller and uses those data to provide quantitative graphs to assess arterial …


Multiobjective Plan Selection Optimization For Traffic Responsive Control, Montasir M. Abbas, Anuj Sharma Apr 2013

Multiobjective Plan Selection Optimization For Traffic Responsive Control, Montasir M. Abbas, Anuj Sharma

Anuj Sharma

Optimal coordination of traffic signals requires proper activation of timing plans to match current traffic conditions. One of the greatest challenges in configuring a traffic responsive plan selection control mode is how to select only n number of timing plans (restricted by traffic controller memory limitations) to address possibly all traffic conditions/states that can be encountered in the field, for a specific site, but most importantly, how to associate each of these traffic conditions to one of the n timing plans stored in the traffic controller. This paper uses a multiobjective non-dominated sorting genetic algorithm to (1) select the best …


Stochastic Algorithm For Improved Operations At Isolated High Speed Intersections, Anuj Sharma, Darcy M. Bullock, Srinivas Peeta Apr 2013

Stochastic Algorithm For Improved Operations At Isolated High Speed Intersections, Anuj Sharma, Darcy M. Bullock, Srinivas Peeta

Anuj Sharma

The current practice of specifying simultaneous gap out logic at isolated high speed signalized intersections places constraints on the signal controller logic that cannot be satisfied under high congestion level. Further, it often results in degraded signal efficiency and dilemma zone protection. A stochastic approach is proposed in this paper with the objective of increasing safety and efficiency at these intersections.


Detection Of Inclement Weather Conditions At A Signalized Intersection Using A Video Image Processing Algorithm, Anuj Sharma, Darcy M. Bullock, Srinivas Peeta, James V. Krogmeier Apr 2013

Detection Of Inclement Weather Conditions At A Signalized Intersection Using A Video Image Processing Algorithm, Anuj Sharma, Darcy M. Bullock, Srinivas Peeta, James V. Krogmeier

Anuj Sharma

Inclement weather conditions like snowfall adversely affect traffic flow characteristics, necessitating a change in parameters that define the operation of a signalized intersection. A weather-based timing plan selection is needed to maintain a desirable level of operational efficiency. Automatic implementation of weather-based timing at intersections requires accurate and timely detection of snowfall. This paper presents a snow detection algorithm that uses live video feed obtained from a video image vehicle detection system present at an intersection.


Configuration Methodology For Traffic-Responsive Plan Selection: A Global Perspective, Montasir M. Abbas, Nadeem A. Chaudhary, Geza Pesti, Anuj Sharma Apr 2013

Configuration Methodology For Traffic-Responsive Plan Selection: A Global Perspective, Montasir M. Abbas, Nadeem A. Chaudhary, Geza Pesti, Anuj Sharma

Anuj Sharma

Although several studies have shown the potential great benefits of traffic-responsive plan selection (TRPS) control, time-of-day operation continues to be the primary method used to select patterns for signal control applications. This practice could be largely attributed to the minimal guidelines available on the setup of the TRPS mode. An innovative framework for TRPS system setup is provided, and guidelines for implementing TRPS in a simplified manner are shown. The guidelines, developed at Texas Transportation Institute (TTI), use a comprehensive approach that incorporates a multiobjective evolutionary algorithm and a supervised discriminant analysis. Engineers can directly implement the guidelines presented as …


Limitations Of Simultaneous Gap-Out Logic, Anuj Sharma, Darcy M. Bullock, Srinivas Peeta Apr 2013

Limitations Of Simultaneous Gap-Out Logic, Anuj Sharma, Darcy M. Bullock, Srinivas Peeta

Anuj Sharma

The current practice of specifying simultaneous gap-out logic places constraints on signal controller logic. These constraints cannot be achieved under high traffic flow conditions, and degraded signal efficiency and dilemma zone protection often result. This study documents the phenomenon described above with set-back detectors at an instrumented intersection in Noblesville, Indiana, and characterizes the problem of dilemma zone protection as being traffic-volume dependent, a factor that should be carefully considered before the simultaneous gap-out logic is applied. Implementation of simultaneous gap-out logic led to max out ranging from 3.5% to 40% of cycles per hour during peak traffic flow periods …


Input-Output And Hybrid Techniques For Real-Time Prediction Of Delay And Maximum Queue Length At Signalized Intersections, Anuj Sharma, Darcy M. Bullock, James A. Bonneson Apr 2013

Input-Output And Hybrid Techniques For Real-Time Prediction Of Delay And Maximum Queue Length At Signalized Intersections, Anuj Sharma, Darcy M. Bullock, James A. Bonneson

Anuj Sharma

Vehicle delay and queue length are quantitative measures of intersection performance. The technological advancement in the field of vehicle sensors and traffic controllers has reached a point where it has enabled efficient measurement of these performance measures. Two techniques are presented for real-time measurement of vehicle delay and queue length at a signalized Intersection, and these automated delay and queue estimates are compared with manually ground-truthed measurement. These techniques were evaluated at an instrumented intersection in Noblesville, Indiana. The root-mean-square error by both techniques was below 0.7 veh-s for-estimation of average delay and less than 0.15 vehicle for estimation of …


Role Of Information On Probability Of Traffic Conflict On The Onset Of Yellow, Nathaniel P. Burnett, Anuj Sharma Apr 2013

Role Of Information On Probability Of Traffic Conflict On The Onset Of Yellow, Nathaniel P. Burnett, Anuj Sharma

Anuj Sharma

This paper examines the effect of information provided to drivers through advance warning flashers (AWFs) on driver’s probability of conflict at the onset of yellow at a high-speed intersection. AWFs are specifically designed to minimize the number of vehicles trapped in their respective dilemma zones at the onset of yellow. A probit modeling technique was used to establish dilemma zone boundaries. Based on the dilemma zone boundaries probability of a perceived conflict curves was computed and compared against actual conflicts observed at each of the studied intersections. The comparison between the actual and theoretical probability of conflict curves generated a …


Pilot Study On Real-Time Calculation Of Arrival Type For Assessment Of Arterial Performance, Edward J. Smaglik, Darcy M. Bullock, Anuj Sharma Apr 2013

Pilot Study On Real-Time Calculation Of Arrival Type For Assessment Of Arterial Performance, Edward J. Smaglik, Darcy M. Bullock, Anuj Sharma

Anuj Sharma

The Highway Capacity Manual uses the arrival type (AT) as a mechanism to account for the quality of traffic signal coordination in the calculation of delay at a signalized intersection. Although there is much discussion in the literature regarding the accuracy and precision of this approach, the AT parameter provides a simple mechanism for grading the performance of traffic signal coordination. This paper describes data collection limitations of current traffic signal controllers and proposes a procedure where the AT parameter can be calculated by traffic signal controllers in real time. Given that the nation received a score of 61 out …


Optimization Of Time Of Day Plan Scheduling Using A Multi-Objective Evolutionary Algorithm, Montasir M. Abbas, Anuj Sharma Apr 2013

Optimization Of Time Of Day Plan Scheduling Using A Multi-Objective Evolutionary Algorithm, Montasir M. Abbas, Anuj Sharma

Anuj Sharma

Coordinating traffic signals can provide great savings to motorists in terms of reduced delays and number of vehicular stops. In order to maximize benefits, engineers need to use a mechanism by which the most optimal timing plans are activated when the traffic patterns change. Common ways of accomplishing this need is by using Time of Day (TOD) plan scheduling, or Traffic Responsive Plan Selection (TRPS). Out of the two modes, the TOD mode is by far the most common. Engineers, however, typically use their judgment to determine the TOD plan scheduling. Unless traffic patterns change at certain times of the …


Performance Requirements And Evaluation Procedures For Advance Wide Area Detectors, Anuj Sharma, Matthew Harding, Brad Giles, Darcy M. Bullock, James R. Sturdevant, Srinivas Peeta Apr 2013

Performance Requirements And Evaluation Procedures For Advance Wide Area Detectors, Anuj Sharma, Matthew Harding, Brad Giles, Darcy M. Bullock, James R. Sturdevant, Srinivas Peeta

Anuj Sharma

Dilemma zone protection ideally requires the exact position and speed of all the vehicles approaching the intersection. However, point detectors, typically used to protect vehicle incursion into the dilemma zone, only provide binary information about the presence or absence of a vehicle at a fixed point in space. The information regarding position and speed of the vehicle in subsequent time steps is extrapolated. The extrapolation error increases with the increase in projection time. Wide area detector (WAD) overcomes this drawback by tracking each vehicle at all times until they move out of range. Such a detector has the potential to …