Transportation Engineering Commons^™

Exploring And Visualizing Spatial Effects And Patterns In Ride-Sourcing Trip Demand And Characteristics, Bishoy Kelleny, Sherif Ishak

Civil & Environmental Engineering Faculty Publications

The complex demand pattern of ride-sourcing remains to be a challenge to transportation modeling practitioners due to the infancy and the inherently dynamic nature of the ride-sourcing system. Spatial effects exploration and analysis protocols can provide informative insights on the underlying structure of demand and trip characteristics. Those protocols can be thought of as an opportunistic strategy to alleviate the complexity and help specifying the appropriate econometric models for the system. Spatial effects exploration is comparable to point pattern analysis, in which, signals from spatial entities, like census tracts, can be analyzed statistically to reveal whether a specific phenomenon respective …

Workshop Outcomes Report: 1st International Workshop On Seismic Resilience Of Arctic Infrastructure And Social Systems, Majid Ghayoomi, Katharine Duderstadt, Alexander Kholodov, Alexander Shiklomanov, Matthew Turner, Elham Ajorlou

Faculty Publications

No abstract provided.

A Deep Machine Learning Approach For Predicting Freeway Work Zone Delay Using Big Data, Abdullah Shabarek

Dissertations

The introduction of deep learning and big data analytics may significantly elevate the performance of traffic speed prediction. Work zones become one of the most critical factors causing congestion impact, which reduces the mobility as well as traffic safety. A comprehensive literature review on existing work zone delay prediction models (i.e., parametric, simulation and non-parametric models) is conducted in this research. The research shows the limitations of each model. Moreover, most previous modeling approaches did not consider user delay for connected freeways when predicting traffic speed under work zone conditions. This research proposes Deep Artificial Neural Network (Deep ANN) and …

High-Speed Rail Safety Analysis Based On Dual-Weighted Complex Network, Liu Lv

Dissertations

This study uses a complex network model to analyze the causes of accidents in high-speed railway operations. By identifying the key factors that led to high-speed railway accidents, hidden safety hazards were discovered. This will help improve the operational safety of the U.S. high-speed rail line under construction.

The analysis uses the regional high-speed railway network in Guangzhou, China as a case study, including the railway (including high-speed railway) accidents that occurred in the company's jurisdiction from 2013 to 2017. With comparative analysis between general railways and high-speed railways, the changes of high-speed railway safety factors are explored. Data analysis …

Incident Duration Time Prediction Using A Supervised Topic Modeling Method, Jihyun Park

Theses

Precisely predicting the duration time of an incident is one of the most prominent components to implement proactive management strategies for traffic congestions caused by an incident. This thesis presents a novel method to predict incident duration time in a timely manner by using an emerging supervised topic modeling method. Based on Natural Language Processing (NLP) techniques, this thesis performs semantic text analyses with text-based incident dataset to train the model. The model is trained with actual 1,466 incident records collected by Korea Expressway Corporation from 2016-2019 by applying a Labeled Latent Dirichlet Allocation(L-LDA) approach. For the training, this thesis …

A Review Of Different Aspects Of Applying Asphalt And Bituminous Mixes Under A Railway Track, Kazem Jadidi, Morteza Esmaeili, Mehdi Kalantari, Mehdi Khalili

Civil and Environmental Engineering and Construction Faculty Research

Asphalt is a common material that is used extensively for roadways. Furthermore, bituminous mixes have been used in railways, both as asphalt and as mortar. Different agencies and research institutes have investigated and suggested various applications. These studies indicate the benefits of bituminous material under railways, such as improving a substructure’s stiffness and bearing capacity; enhancing its dynamic characteristics and response, especially under high-speed train loads; waterproofing the subgrade; protecting the top layers against fine contamination. These potential applications can improve the overall track structure performance and lead to minimizing settlement under heavy loads. They can also guarantee an appropriate …

Direct Predictive Speed Control Of Salient Pmsm Drives In Constant Torque And Constant Power Regimes For Electric Vehicles Applications, Francis Mwasilu

Tanzania Journal of Engineering and Technology (TJET)

A direct speed control of salient permanent magnet synchronous motor (PMSM) drives in constant torque and constant power regimes for electric vehicles applications is presented. The proposed speed control scheme is derived from model predictive control approach where both rotor speed and stator current are formulated in a single objective function that is periodically computed to attain the PMSM drive optimum switching states. The dynamic model of the PMSM intrinsically encompasses the unknown disturbance, which should be rejected for high-performance speed control especially in transient conditions. Consequently, the extended modified augmented state Kalman filter (ASKF) is incorporated in the proposed …

Research On Weather Conditions And Their Relationship To Crashes, Mark R. Anderson, Aemal Khattak, Muhammad Umer Farooq, John Cecava, Curtis L. Walker

Nebraska Department of Transportation: Research Reports

The objectives of the research were to conduct a seasonal investigation of when winter weather conditions are a factor in crashes reported in Nebraska, to perform statistical analyses on Nebraska crash and meteorological data and identify weather conditions causing the significant safety concerns, and to investigate whether knowing the snowfall amount and/or storm intensity/severity could be a precursor to the number and severity of crashes.

Nebraska Department of Transportation (NDOT) crash data were combined with meteorological data on winter weather season basis, reported road surface condition at crash time, and reported weather conditions at crash time. Overall, the key finding …

Nebraska Rail Crossing Safety Research, Aemal Khattak, Yashu Kang, Huiyuan Liu

Nebraska Department of Transportation: Research Reports

The research objectives of this project were to update Nebraska Department of Transportation (NDOT) 1999 Nebraska Accident Prediction Model for Highway-Rail Grade Crossings (HRGCs) and to develop guidelines using Lancaster County Nebraska HRGCs for improving safety at urban gated HRGCs that are not designated quiet zones but are in the vicinity of quiet zone crossings.

FRA crash and HRGC inventory data were utilized for estimation of the new model after inventory information on 742 HRGCs was updated. HRGC crashes for 2008-2018 period were used for model estimation while 2019 HRGC crashes were used for model prediction validation. After consideration of …

To Automate Detecting, Quantifying And Mapping Of Delamination Via Arial Thermography, Ziqi Shen, Chongsheng Cheng, Ri Na, Zhexiong Shang

Nebraska Department of Transportation: Research Reports

The goal of this project is to develop a UAV-based Arial thermographic method to detect and map the delamination on concrete bridge decks. Several image processing methods such as level-set and machine-learning were developed in this project. The developed method is high-efficient and low-cost and requires no-traffic-closure during the surveying process. The coring outcomes from four different concrete bride decks validated the performance of this developed method. The coring results suggested that this method outperformed several existing methods in detecting delamination in concrete bridge decks in terms of efficiency, accuracy, cost, and safety.

High-Mast Tower Foundation, Chungwook Sim, Chung R. Song, Brandon Kreiling, Jay Puckett

Nebraska Department of Transportation: Research Reports

High-Mast Tower (HMT) foundations have been traditionally designed and constructed using cast-in-place foundation with anchor bolts that are used to secure the tower to the foundation. This type of design requires a base plate that is welded to the tower shaft. The Nebraska Department of Transportation (NDOT) has recently experienced issues with stresses that this type of design presents at the anchor bolt/foundation or base plate/tower shaft interface. This issue in worst cases may lead to a premature failure due to high-cycle fatigue as one of the towers at Milford, Nebraska that fell down during a winter snow storm event …

Problems And Ways Of Solution In Transit Of Automobile Transport Of The Republic Of Uzbekistan, Aziz S. Khalmukhamedov

Acta of Turin Polytechnic University in Tashkent

Maintaining the transit potential of a country is an integral part of the transport program of any country and vital for the economy. Unsatisfactory transit potential negatively affects the economy. Therefore, it is necessary to survey and establish indicators of the country’s transit potential. The determining factor of the country’s transit potential is the level and condition of the country’s highways. Thus, the indicator of the quality of the road - the flatness of the road - can become the main indicator that can be used for a generalized and quick assessment of the characteristics of the country’s transit potential. …

Data Analysis Of Nebraska Pavements Containing Rap, Abdullah Azzam, Yong-Rak Kim, Mohammad Rahmani, Jiong Hu

Nebraska Department of Transportation: Research Reports

Nebraska has used reclaimed asphalt pavement (RAP) materials (in a range of 20-50%) over more than 10 years in pavement construction. Despite the immediate economic and environmental benefits it has been reported that incorporating RAP may reduce pavement durability and crack resistance. This study used NDOT’s database to investigate the effect of RAP amount on the overall behavior of pavement performance. Toward that end, we collected data of pavement performance, mixture design, traffic, and environment of a total 254 pavement projects constructed between 2009 and 2012. Using the data, several analyses (such as descriptive, inferential, and life cycle cost) were …

Expanding The Concept Of Comprehensive Area Ratio Parameter To The South-Central States Towards Simplifying The Structural Evaluation Of Flexible Pavements At The Network Level, Nitish R. Bastola

Civil Engineering Theses

The surface deflection bowl data collected through Non-Destructive Testing (NDT) has been widely utilized by various Department of Transportation (DOTs) in the South-Central States and other places. The primary purpose of using deflection-based NDTs in network-level assessment is to identify a weak pavement section that requires further analysis at the project level. The falling weight deflectometer (FWD) test is one of the common NDT based tests utilized by highway agencies in assessing the performance of the flexible pavement. However, a robust method to evaluate pavement sections utilizing FWD data from all the sensors are seldom developed. There is always a …

Laboratory Testing And Mechanistic Analysis Of Treated Subgrade Soils, Hari Kumar Reddy Yarrapureddi

Civil Engineering Theses

Calcium-based stabilizing agents such as cement and lime have been extensively used to improve the engineering properties of base and subgrade layers of pavement systems. Recently, polymers and chemical stabilizers have become popular due to cost efficiency, ease of application, and fast curing times. In this study, California Bearing Ratio (CBR) values of polymer and chemical treated soils were compared with the CBR values of soils treated with conventional stabilizers. Parametric sensitivity analyses was carried out on key parameters including the type of subgrade soil, stabilizing agent, stabilizing agent treatment levels, and moisture conditioning. Additionally, numerical analyses was performed to …

Challenges And Suggestions Of Diesel Oil Cleaning System In Unmanned Surface Vessels, Liwei Zhang

Maritime Safety & Environment Management Dissertations (Dalian)

No abstract provided.

Research On Risk Identification, Evaluation And Countermeasures Of Liquid Dangerous Cargo Ships In Yangpu Waters, Xiaofeng Han

Maritime Safety & Environment Management Dissertations (Dalian)

No abstract provided.

Bio-Binder—Innovative Asphalt Technology, Amir Tabakovic

Articles

The global road network spans 16.3 million km [1], of which 5 million km is in the EU. These road networks fulfil major economic and social goals by facilitating the movement of goods and people throughout the EU, and are therefore of the utmost importance to the economic and social life of the EU [2]. National governments invest heavily in their road networks, e.g., in 2014, EUR 53.33 billion was invested in the development and maintenance of the EU road network [3]. Each year, the world produces 1.6 trillion tonnes of asphalt [4], of which 218 million tonnes is produced …

Cement Stabilized Crushed Stone Base Course Strength And Stiffness Analysis, Andrew Deschenes

Graduate Theses and Dissertations

Approximately 70 – 80% of state departments of transportations (DOTs) utilize the 1993 AASTHO Guide for Design of Pavement Structures (1993 AASHTO) [1] for structural design of pavements. A growing portion of DOT’s are beginning to implement the Mechanistic-Empirical Pavement Design Guide (MEPDG), referred to as AASHTOWare Pavement ME [2]. The 1993 AASHTO flexible guide applies empirically derived unitless strength values referred to as structural layer coefficients and structural numbers (SN) to pavement thickness and pavement types. The 1993 AASHTO rigid flexible guide utilizes the depth and strength of the concrete pavement, with the composite spring constant (kc), which is …

An Investigation Into The Effects Of Fly Ash On Freeze-Thaw Durability Prediction, Yancy Schrader

Graduate Theses and Dissertations

Air is purposefully entrained into concrete primarily to improve resistance to freeze-thaw deterioration while saturated with water. Air entraining admixtures (AEAs) are chemical admixtures designed to entrain air into the concrete to provide adequate resistance to the effects of freezing and thawing. One of the challenges associated with air entrainment in concrete is the interaction of an AEA with supplementary cementitious materials present in the concrete, particularly fly ash. Fly ash is a by-product of the coal fired electrical generation industry, and often contains residual unburned carbon and other components that can increase the AEA demand of a particular concrete …