Transportation Engineering Commons^™

Study On Modification Of Phosphate Pretreated Aggregate Vegetation Porous Concrete, Li Zhengxing, Hou Zebiao

Journal of China & Foreign Highway

To enhance the interfacial structure between aggregates and cementitious materials in vegetation porous concrete and improve its compressive strength, this paper investigates the effects of phosphate pretreatment on aggregate properties and the corresponding compressive strength of vegetation porous concrete. The performance of untreated aggregates, water-washed aggregates, and acid-treated aggregates was evaluated, and the modification mechanism was explored from the perspective of the interfacial transition zone (ITZ) using scanning electron microscopy (SEM). The results show that phosphate effectively removes impurities from the aggregate surface and increases surface roughness, thus improving the compactness and stability of the ITZ. After soaking the aggregates …

Optimization Study On Indoor Vibratory Compaction Curves Of Cement Stabilized Macadam, Qiu Youqiang, Zhang Liujun

Journal of China & Foreign Highway

To obtain well-defined secondary convex vibratory compaction curves and reduce the need for supplemental compaction point tests, this paper uses vibratory compaction tests for cement stabilized macadam in laboratory settings. Tests were conducted for two pavement sections along National Highway 110 (Hohhot to Bikeqi), exploring the influence of predefined moisture content intervals on vibratory compaction curves under varying cement dosages. The vibratory compaction curves were also compared with heavy compaction curves for analysis. The results show that the vibratory compaction curve is significantly influenced by the predefined moisture content intervals and cement dosage. For a moisture content interval of 1%, …

Selection Of Phase Change Materials For Asphalt Pavement Based On Molecular Dynamics Simulation, Liu Fujun, Tian Xin, Liang Meichen, Guo Meng

Journal of China & Foreign Highway

Phase change materials (PCMs) have significant application potential in temperature regulation for asphalt pavements. To select suitable PCMs for road applications, this paper utilizes molecular dynamics simulation to analyze the molecular behaviors of lauric acid and polyethylene glycol (PEG). Experimental studies were conducted to validate the simulation results. The results show that molecular dynamics simulation provides an efficient and convenient method for comparing the performance of PCMs. PEG outperforms lauric acid in terms of molecular density, cohesive energy density, solubility parameters, and thermal conductivity, making it more suitable as a phase change material for asphalt pavements.

Experimental Study On Water Stability Of Sand Compound Modified Mud Road, Chai Ruixiang, Wu Kai, Ye Wei, Cui Jinmei, Wang Jicheng, Li Zhantao

Journal of China & Foreign Highway

Sand compound modified mud, as a coupled medium of sand and soil, differs from traditional modified mud. To further investigate its water stability indicators, orthogonal design was employed to conduct indoor water stability simulation tests (surface infiltration test, underground capillary water test, and dry-wet cycle test) on sand compound modified mud. The water stability of the modified mud was characterized using the change rate of unconfined compressive strength (UCS). The results show that the unconfined compressive strength and water stability of the modified mud were significantly improved. Under different water disturbance conditions, the order of influence of factors such as …

Experimental Study On Influence Of Phosphorus Slag Powder On Pervious Concrete, Lou Jianxin, Yang Jianyong, Zhang Yuxian, Li Jun, Wang Jie, Liu Jian

Journal of China & Foreign Highway

This paper investigates the effects of replacing cement with phosphorus slag powder on the mechanical properties, permeability, and pavement performance of pervious concrete. The results show that incorporating a certain amount of phosphorus slag powder as a partial replacement for cement in pervious concrete is feasible. When the replacement ratio of phosphorus slag powder is within 10%, it enhances the strength of pervious concrete. The optimal replacement ratio of phosphorus slag powder is 8%, achieving a compressive strength of 24.18 MPa, a void ratio of 15.37%, and a permeability coefficient of 2.45 mm/s, which meet the requirements for fully permeable …

Study On Alkali Excitation Mechanism Of Large Dosage Slag Fine Powder, Mei Yang

Journal of China & Foreign Highway

To reveal the alkali excitation mechanism of high-dosage slag, this paper combines a three-factor, three-level orthogonal design with macro- and micro-performance tests and microstructure analysis. The effects of different activators, including Ca(OH)2, Na2SiO3, Na2SO4, and CaSO4, in single and dual combinations on the initial and final setting times, pore solution pH, and strength of concrete were explored. The results show that the impact on the strength of hardened paste of composite cementitious materials is ranked as: activator type > dosage > dual-mix ratio. The optimal dual-mix dosage is 4%, with the best combination being Ca(OH)2 and Na2SiO3 at a ratio of 5:1. …

Dynamic Load Response Analysis Of Rubber Powder Modified Asphalt Mixture, Yang Sanqiang, Sun Shuang, Li Qian, Liu Xinlei, Qin Lusheng

Journal of China & Foreign Highway

To investigate the mechanical response of rubber powder modified asphalt pavement under dynamic loads, this paper, based on the “Full-Scale Accelerated Pavement Loading Testing” project, designed experimental schemes for asphalt mixtures with varying rubber powder contents. The paper employed accelerated loading test equipment to evaluate the stress and deformation of pavement structures, obtaining dynamic strain response data to analyze the strain response patterns of various structural layers. Combining finite element numerical simulations and a custom loading program, the paper examined the dynamic responses of rubber powder modified asphalt pavements under variable temperature conditions. The results show that through microscopic testing, …

Aging Asphalt Concrete Cracking Performance Under Different Cyclic Loading Frequencies, Yan Jingchen, Ma Yanpei, Yan Junjie

Journal of China & Foreign Highway

Using digital speckle technology, this paper examines the crack propagation behavior of asphalt concrete under repeated loading, analyzing the crack propagation mechanism from macro- and micro-perspectives under different aging conditions and loading frequencies for four types of asphalt concrete. The results show that the basalt fiber-reinforced asphalt concrete beam specimens delay the onset of the unstable crack propagation phase, thus extending the service life of the asphalt concrete. Aging accelerates the progression of asphalt concrete to the unstable crack propagation point, advancing this stage by 4%-5%. Under repeated loading frequencies of 5 Hz, 10 Hz, and 15 Hz, the damage …

Study On Microstructure Of Asphalt Modified By Oil‐Coal Blend, Guo Pengfei, Zhou Xinfeng

Journal of China & Foreign Highway

To investigate the microstructure and modification mechanism of asphalt modified with oil-coal blend, SK-90# asphalt was mixed with 5%, 10%, 15%, 20%, and 25% (external blending method) oil-coal blend to produce modified asphalt. The performance and microstructural changes of the modified asphalt were analyzed using contact angle testing, infrared spectroscopy, cross-sectional SEM, and X-ray photoelectron spectroscopy. The results show that the oil-coal blend exhibits good compatibility with asphalt. During the modification process, esterification reactions occurred, resulting in a decrease in hydroxyl-containing aromatic compounds and an increase in carbonyl-containing aromatic compounds. Macroscopically, the oil-coal blend-modified asphalt demonstrated excellent high-temperature performance.

Design And Development Of Two And Three Dimensional Integration System For Highway Based On Webgis, Che Defu, Zhou Huajun

Journal of China & Foreign Highway

To address the inefficiencies, lengthy cycles, and high resource demands in the process of determining the annual project database for highway maintenance quotas in Liaoning Province, a 2D and 3D integration system for highways based on WebGIS was designed and developed. This system not only provides a macroscopic view of the geographic distribution and overall characteristics of highways but also offers a detailed and intuitive representation of the spatial relationships and conditions of roadbeds and pavement damage. The system meets the needs of modern highway management and can serve as a reference for other highway maintenance quota tasks.

Research On Influence Factors And Efficiency Analysis Of Expressway Maintenance Marketization, Zhong Wen, He Shoukui, Wang Xiaodong

Journal of China & Foreign Highway

To promote market-oriented reform of highway maintenance, this paper investigates its influencing factors and outcomes and proposes an evaluation model for assessing its effects. A panoramic analysis method within a three-dimensional framework was employed to determine the evaluation content. Drawing on the balanced scorecard concept, the analysis incorporates four dimensions: business, user, internal management, and learning and growth, with the innovative addition of a social responsibility dimension to construct an evaluation indicator system. Subsequently, a cloud-based extension model was developed to evaluate the effectiveness of expressway maintenance marketization and calculate the evaluation grade. Empirical analysis was conducted using data from …

Analysis Of Expressway Routine Maintenance Performance Management Based On Dea, Li Yuhuan, Shi Xiaoli, Gao Nan

Journal of China & Foreign Highway

To allocate maintenance resources efficiently and improve management levels, this paper examines the maintenance performance and improvement strategies of routine maintenance projects for 23 expressways in Shaanxi Province using 2018 operational maintenance data and data envelopment analysis. The results show that for some inefficient subsidiaries, traditional radial- and slack-based performance improvement methods are challenging and impractical in the short term. Therefore, a scenario-dependent model-based long-term incremental improvement strategy is proposed. By leveraging relative improvement values, this strategy enables phased improvements for inefficient subsidiaries. It provides a feasible approach for subsidiaries to set lower short-term performance improvement targets while achieving gradual …

Study On The Minimum Radius Of Vertical Curve Of Highway Main Line Entrance Section Based On Merging Sight Distance, Li Yang, Zhao Yemei, Chen Tianxing

Journal of China & Foreign Highway

Given the limited research on the vertical curve radius of highway mainline entrance sections and the lack of differentiation between entrance and exit sections in existing studies, this paper identifies merging sight distance as the primary influencing factor for the vertical curve radius of entrance sections. Using merging sight distance as the control condition, the vertical curve radius of entrance sections was studied. A safety merging sight distance calculation model for highway mainline entrance sections was established by analyzing the traffic behavior characteristics of vehicles on the entrance mainline and considering drivers’ psychological and physiological characteristics. The sight distance model …

Optimization Of The Self-Healing Efficiency Of Bacterial Concrete Using Impregnation Of Three Different Precursors Into Lightweight Aggregate, Omar Omar

LSU Master's Theses

Concrete is the most broadly used construction material; thus, developing sustainable concrete is essential to decrease greenhouse gas (GHG) emissions from concrete production. Implementation of self-healing concrete technologies is a promising approach to enhance the durability and sustainability of the transportation infrastructure. Among these technologies, bacterial concrete has the potential to seal microcracks through microbial induced calcite precipitation (MICP). Bacterial protection is essential to ensure the viability of this technology due to concrete’s harsh environment. Additionally, the success of this technology depends on the presence of an adequate mineral precursor compound and nutrient for the bacteria. As such, the main …

The Effects Of Inaccurate And Missing Highway-Rail Grade Crossing Inventory Data On Crash And Severity Model Estimation And Prediction, Muhammad Umer Farooq

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

Highway-Rail Grade Crossings (HRGCs) present a significant safety risk to motorists, pedestrians, and train passengers as they are intersections where roads and railways intersect. Every year, HRGCs in the US experience a high number of crashes leading to injuries and fatalities. Estimations of crash and severity models for HRGCs provide insights into safety and mitigation of the risk posed by such incidents. The accuracy of these models plays a vital role in predicting future crashes at these crossings, enabling necessary safety measures to be taken proactively.

In the United States, most of these models rely on the Federal Railroad Administration's …

Safety And Operational Assessment Of Rural Free Right-Turn Ramp Intersections, Jonathon Camenzind

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

Free right-turn (FRT) ramps are alternative right-turn lane designs for intersecting highways. As of 2023, 79 FRT ramps exist at 68 rural highway intersections in Nebraska. FRT ramps may be located on three-legged or four-legged intersections and may be on the minor, the major, or both minor and major approaches of the same intersection.

This research compared the 68 rural FRT intersections to 24 similar non-FRT rural intersections to identify differences in crash frequency and crash rate and tested for statistical significance using a two-sample t-test. Crash data were obtained for the ten- year period of 2010-2019, with a focus …

Smart Transportation In Small- And Medium-Sized Cities In Central California, Hongwei Dong

Mineta Transportation Institute

The research on smart transportation in the United States has centered on large metropolitan areas. The adoption of smart transportation technologies in small-and medium-sized cities outside of large metropolitan areas is less studied and understood. This study examined the adoption of smart transportation technologies in small-and medium-sized cities in Central California. The analysis was based on the online survey responses from 29 transportation officials and professionals who worked for 18 municipal government departments and six metropolitan planning organizations (MPOs) in Central California as well as in depth semi-structured interviews with seven of them. The study showed that smart transportation in …

Feasibility Study: Application Of Steel Sheet-Piles For The Abutment Of Water-Crossing Bridges In Nebraska, Seunghee Kim, Jongwan Eun, Chung R. Song, Chungwook Sim, Hung Phi Van, Basil Abualshar, Ramin Ziaei Tabari

Nebraska Department of Transportation: Research Reports

The overall goal of this study is to investigate the anticipated performance of steel sheet-pile bridge abutments to encourage its wider application to not only new construction but also repair and replacement of existing water-crossing bridges in Nebraska. For this purpose, this study first reviewed several bridge cases with axially loaded sheet pile abutments, as well as previous in-depth studies related to the bearing capacity of sheet piles. Then, this study conducted the large-scale direct shear tests to better understand the interaction between sheet pile and soil. As a result, about four-fifths of the internal friction angle of fill sand …

Impacts Of Diagonal Crosswalk Misuse, Elizabeth Francis

Civil Engineering Undergraduate Honors Theses

A diagonal crosswalk paired with an all-red phase traffic signal is an effective approach to manage intersections with high pedestrian volume. This allows pedestrians to cross both north-south and east-west bound roads at the same time. However, ineffective diagonal crosswalk marking, and lack of signs reduces the use of diagonal crosswalks which in turn results in jaywalking, often in unsafe capacities. The objective of this study is to determine the impacts of pedestrian-caused delay and safety impacts due to the misuse of a diagonal crosswalk. To better understand the impacts, a camera-based data collection was conducted during a four-hour period …

Fiscal Year 2021 Fhwa-536 Report For The Kentucky Transportation Cabinet, Doug Kreis, Candice Wallace, Bryan Gibson, Sarah Mccormack

Kentucky Transportation Center Research Report

No abstract provided.

Development And Evaluation Of Machine Learning Models For Fugitive Methane Detection And Intensity Prediction, Jacquan Pollard

All Theses

The environmental impacts of global warming driven by fugitive methane (CH4) emissions have catalyzed significant research initiatives in developing novel technologies that enable proactive and rapid detection of CH4 emissions. This study evaluated the performance of data-driven machine learning (ML) models using support vector machines (SVM) to detect the presence of trace CH4 emissions and the corresponding intensity amongst various meteorological conditions. The author used simulation data comprising various meteorological parameters such as temperature, relative humidity, wind speed, water vapor, pressure, precipitation rate, and a parameter possessing trace concentrations of CH4 emissions. The novelty of the SVM models developed in …

Quantum Artificial Intelligence Supported Autonomous Truck Platooning, Pronab Kumar Biswas

All Theses

Truck platooning can potentially increase the operational efficiency of freight movement on U.S. corridors, improving commercial productivity and economic vibrancy. Predicting each leader vehicle trajectory in the autonomous truck platoon using Artificial Intelligence (AI) can enhance platoon efficiency and safety. Reliance on classical AI may not be efficient for this purpose as it will increase the computational burden for each truck in the platoon. However, Quantum Artificial Intelligence (AI) can be used in this scenario to enhance learning efficiency, learning capacity, and run-time improvements. This study developed and evaluated a Long Short-Term Memory Networks (LSTM) model and a hybrid quantum-classical …

Piezoresistivity Of Electrically Conductive Asphalt Concrete, Mateo Schmit Mendoza

Theses and Dissertations

Electrically conductive asphalt concrete is considered as a multifunctional construction material due to its structural and non-structural functions. This study aims to investigate piezoresistivity of conductive asphalt concrete. Piezoresistivity is an electrical property of some materials which electrical resistivity changes with induced strain and subsequently, it has the potential for self-sensing smart technology. Graphite Powder F-516 with various contents was added into the asphalt mixtures to impart the electrical conductivity. Electrochemical impedance spectroscopy (EIS) was selected to measure the electrical properties of the specimens in dry and wet conditions, and low and high temperatures. The impedance measurement shows that the …

Studying Pedestrian’S Unmarked Midblock Crossing Behavior On A Multilane Road When Interacting With Autonomous Vehicles Using Virtual Reality, Fengjiao Zou

All Dissertations

This dissertation focuses on the challenge of pedestrian interaction with autonomous vehicles (AVs) at unmarked midblock locations where the right-of-way is unspecified. A virtual reality (VR) simulation was developed to replicate an urban unmarked midblock environment where pedestrians cross a four-lane arterial roadway and interact with AVs. One research goal is to investigate the impact of roadway centerline features (undivided, two-way left-turn lane, and median) and AV operational schemes portrayed through on-vehicle signals (no signal, yellow negotiating indication, and yellow/blue negotiating/no-yield indications) on pedestrian crossing behavior. Results demonstrate that both roadway centerline design features and AV operations and signaling show …

Experimental Investigation Of The Self-Healing Potential Of Bacteria For Sustainable Concrete Structures, Pitiporn Asvapathanagul, Simone Galano, Andrea Calabrese, Mehran Rahmani, Maggie Ly, Daniela Flores, Michael Hernandez, Nicholas Banuelos

Mineta Transportation Institute

Although concrete is the most widely used building material in the world, its limited tensile strength makes cracking a common phenomenon in concrete elements. This study investigates the potential of autonomous self-healing as an eco-friendly and lowcost method to increase the durability of concrete. The crack-healing potential of different types of high-alkaline-tolerant bacteria or calcite-precipitation microorganisms is investigated. High-alkaline-tolerant bacteria and calcite-precipitation microorganisms were used to retrofit lab-fractured concrete samples. The samples healed with each of these bacteria groups were cast and tested under compressive load up to failure to measure the compressive strength of the concrete samples. The outcomes …

Preconstruction Support Cost Hours Estimating On Caltrans Pavement Rehabilitation Projects, Nigel Blampied, Tariq Shehab, Elhami Nasr, Laxmi Sindhu Samudrala

Mineta Transportation Institute

Because the construction phase accounts for the majority of project costs for pavement rehabilitation projects, most research on infrastructure project cost estimating focuses on that phase, rather than on the preconstruction phases. Nevertheless, costs incurred prior to construction, referred to in this report as "preconstruction costs" are significant and worthy of consideration (See Section 2.1 of the report for a more detailed and precise definition of preconstruction). In the 20202021 fiscal year, for instance, the California Department of Transportation (Caltrans) spent more than $169 million on preconstruction work for pavement rehabilitation projects. This report presents the results of a study …

Historic Downtown Streetscape Plan Price City, Utah, Patricia Beckert

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The idea of a small-town Main Street has profound meaning within the American culture that has prevailed for the past two centuries. Historically, Main Street serves as the beating heart of a community, a place where economic, social, cultural, and civic activities are centered (Francaviglia, 1996; Main Street America, n.d.). Since the beginning of the 19th century, many factors have led to the decline of Main Streets, and despite a variety of efforts from different stakeholders, that decline has only intensified in recent decades (Isenberg, 2008; Orvell, 2014 Howard, 2015). In 1980, after a three-year project conducted by the National …

Assessment Of Bridge Pier Response To Fire, Vehicle Impact, And Air Blast, Chen Fang, Qusai Alomari, Daniel G. Linzell

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

Highway bridges exposed to intentional or unintentional fire followed by combined vehicle impact and air blast are at risk of significant damage and, possibly, collapse. Limited studies examining the complex effects of these extreme demands on bridge support elements and parametrizing their response and damage are found in the open literature. Research that is presented is part of an ongoing numerical investigation examining round, multi-column, reinforced concrete (RC), bridge pier behavior subject to multi-hazard scenarios involving fire, vehicle impact, and air blast. Detailed nonlinear finite element analysis models of single columns and multi-column piers supported by a pile foundation system …

Electric Vehicle Routing Problem – Models And Algorithms, Hesamoddin Tahami

Engineering Management & Systems Engineering Theses & Dissertations

The transportation sector is a major greenhouse gas emitter that is heavily regulated to reduce its dependence on oil. These regulations along with the growing customer awareness of global warming have led to the investigation of new transportation problems that consider using eco-friendly vehicle fleets. Promising alternatives to traditional fleets include alternative fuel vehicles (AFVs) and electric vehicles (EVs). These twenty-first-century vehicles offer an appealing advantage of consistently reducing their environmental impact, but due to the current technology, they exhibit bothersome limitations. The short driving range along with limited charging infrastructure may consequently cause issues related to range anxiety, i.e., …

Investigating The Severity And Rate Of Occurrence Of Motorcycle Crashes Across Different Land Uses In Georgia, Robert Edwards

Symposium of Student Scholars

In 2020, motorcycle crashes reached their highest number of fatalities nationally since 1975, when 5,579 motorcyclists were killed. Georgia, in recent years, has seen an increase in the number of fatal multi-vehicle crashes involving motorcycles. This would be indicative of the general trend and nothing more if the number of motorcycle crashes reported outside of urban populations did not increase—despite lockdown measures—by 1.7% in 2020. In this investigation, employing a thorough examination of the Georgia Department of Transportation’s Crash Data (GDOT) compiled from the last ten years and the Fatality Analysis Reporting System (FARS) compiled from the last five years, …