Engineering Commons^™

Multi-Objective Optimization Of A Ridesharing System Performance, Mohammad Nasr Azadani

Graduate Theses, Dissertations, and Problem Reports

Ridesharing is a shared vehicle service with the potential to meet the growing travel demand due to population increase, economic growth, and shortage in transportation infrastructure capacity. Compared to the current system of predominantly using personal vehicles, ridesharing services reduce the number of vehicles while providing mobility services to the same number of people with no additional investment in the transportation infrastructure. One of the big challenges in implementing ridesharing services is matching drivers and riders. Conflicts between matching-objectives to comply with the interests of diverse stakeholders influence the efficiency of ridesharing in a transportation system. This study investigates the …

Effect Of Binder Modification And Aggregate Size On Modulus And Fatigue Of Asphalt Concrete, Elizabeth Bashiti

Graduate Theses, Dissertations, and Problem Reports

Asphalt concrete is one of the main ingredients used in the paving of roadways across the globe. These roadways have been deteriorating from overuse, under design, and a lack of understanding of the engineering properties. In the asphalt community, it is agreed upon that polymer modifiers and aggregate size have comparable impacts on the performance of a pavement, such as, low creep at high temperatures, high ductility at low temperatures, high toughness, resistance to moisture and temperature, high cohesive and adhesive strength. With all of these advantages, it has been often assumed that polymer modifiers extend/improve the expected life of …

Evaluation Of Test Specimen Geometry Of Asphalt Mixes Tested With The Asphalt Mixture Performance Tester, Abha Dwivedy

Graduate Theses, Dissertations, and Problem Reports

Asphalt concrete, AC, is a heterogeneous material that is modeled as a homogeneous material. The disparity between material structure and theory presents issue with performance testing with test sample geometries, resulting in variability. The purpose of this research is to develop appropriate sample geometry for AMPT test for accurate characterization of asphalt mix and ease of testing.

Four sample geometries were fabricated for three mix types. All specimens are fabricated at 7%0.5% air voids and tested for AMPT tests. The effect of sample geometry was statistically analyzed using laboratory test results and performance predictions using FlexPAVE. For ranking analysis all …

On-Site Measurement Of The Water-Cementitious Ratio And Heat Of Hydration Of Delivered Concrete, Seyednavid Mardmomen

Graduate Theses, Dissertations, and Problem Reports

In this study, AASHTO T318-15 was adopted to estimate the water content of fresh concrete mixes and then revised to have better precision. The additional step required sieving out the coarse aggregate after drying the sample in a microwave oven, and it was then used in the calculation of the absorbed water and cementitious material content. Several laboratory batches, as well as on-site water-cementitious (w/cm) ratio tests, were performed on concrete mixes containing ordinary Portland cement, ground granulated blast furnace slag, and Class F fly ash. The results of the experiments indicated that the accuracy of the revised method was …

Evaluating The Polishing Of Skid Aggregates In Asphalt Using The British Pendulum Tester, Allison Nicole Givens

Graduate Theses, Dissertations, and Problem Reports

To ensure the pavements in West Virginia have adequate skid resistance the Division of Highways evaluates and approves skid resistant aggregate sources for all wearing courses on roads with an ADT of 3,000 or greater. Unfortunately, the supply of skid aggregates in West Virginia is depleting quickly. To find a potential alternative to using skid resistant aggregates, laboratory polishing of asphalt samples was performed using a Circular Track Polishing Machine, and friction was tested using a British Pendulum Tester. The experiment was designed to investigate how a specific aggregate type provides skid resistance to a hot asphalt mixture.

The objective …

Impacts Of Bike Sharing On Transit Ridership, Moathe Salah Aljeri

Graduate Theses, Dissertations, and Problem Reports

Biking is an active, environmentally friendly, and sustainable transportation mode that facilitates short utilitarian and recreational trips. As such, cities around the world have been implementing bicycle sharing/renting programs at stations in a wide network so that a traveler can mount one close to their origins and drop it off at a station nearest to their destinations. In addition, bike sharing programs can solve the first-mile and last-mile connectivity problems of transit modes. Such programs also enable short trips that were previously impossible without using transit modes. This research investigated the relationship between New York City (NYC) subway ridership and …

Field Evaluation Of A Modular Press-Brake-Formed Steel Tub Girder In An Application That Includes Skew And Superelevation, Adam D. Roh

Graduate Theses, Dissertations, and Problem Reports

The Short Span Steel Bridge Alliance (SSSBA) is a group of bridge and culvert industry leaders (including steel manufacturers, fabricators, service centers, coaters, researchers, and representatives of related associations and government organizations) who have joined together to provide educational information on the design and construction of short span steel bridges in installations up to 140’-0” in length. A technical working group from within the SSSBA developed the notion for the modular shallow press-brake-formed steel tub girder as a solution for the short span steel bridge market.

After extensive testing at West Virginia University and multiple successful field demonstrations, members of …

Procedure For Asphalt Mixture Friction Evaluation For Wvdoh, Danielle Marie Hoyer

Graduate Theses, Dissertations, and Problem Reports

Monitoring asphalt skid resistance in the laboratory could aid in improved friction prediction capabilities and provide insight for developing alternative asphalt mixture designs in the future. The West Virginia Department of Highways (WVDOH) sought the design of a laboratory accelerated asphalt polishing machine to further expand on current skid resistance measurement practices. The design is modeled after the North Carolina State University (NCSU) polishing machine detailed in ASTM E660. The purpose of this research was to develop a testing procedure for the polishing equipment. Friction was monitored with the British Pendulum Tester (BPT) according to ASTM E303.

Specimens were prepared …

Transit Agencies Performance Assessment And Implications, Parisa Hajibabaee

Graduate Theses, Dissertations, and Problem Reports

Although most transit systems operate in small urban and rural areas in the United States, these systems have rarely received the same attention as their urban counterparts, both in terms of ensuring the efficiency and effectiveness of their operations and understanding the factors that affect their performance. This thesis's main goals are to assess the performance of rural and small urban public transit agencies and help them evaluate adopting a ridehailing program, thereby improving their performance. We applied operations research and decision-making tools to two public transit projects in small urban and rural areas. The first project focuses on three …