Theses and Dissertations at Montana State University (MSU)

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Feasibility of non-proprietary Ultra-High Performance Concrete (UHPC) for use in highway bridges in Montana: phase III implementation
(Montana State University - Bozeman, College of Engineering, 2022) Hendricks, Elias Michel; Chairperson, Graduate Committee: Michael Berry
Ultra-high performance concrete (UHPC) has mechanical and durability properties that far exceed those of conventional concrete. However, using UHPC in conventional concrete applications has been cost prohibitive, with commercially available/proprietary mixes costing approximately 30 times more than conventional concrete. Previous research conducted at MSU developed a nonproprietary UHPC mix design (MT-UHPC) that is significantly less expensive than commercially available mixes and is made with materials readily available in Montana. The focus of the research discussed herein was on the field implementation of MT-UHPC. Specifically, MT-UHPC was used in all field-cast joints on two bridges spanning Trail Creek on Highway 43 outside of Wisdom, MT. This project began with an extensive literature review focused on previous field applications of UHPC. Subsequently, implementation research was performed with the intent of filling several research gaps related to the field application of MT-UHPC. This research investigated the effects that mixing process, batch size, and temperature have on the performance of MT-UHPC. It also developed maturity curves to be used in estimating the early strength gain of MT-UHPC. Trial batches were then conducted on site and placed into joint mockups to confirm and improve the construction methods to be used on the actual bridge project. In this exercise MT-UHPC was mixed using the same methods and under the same environmental conditions expected on the day of construction. MTUHPC was then used in the Trail Creek bridges to connect the precast concrete bridge elements. Overall, this project was a successful demonstration of using a nonproprietary UHPC in field-cast joints for an accelerated bridge construction (ABC) project. All placed UHPC had adequate flows, gained strength quickly, and reached the required minimum compressive strengths. This was accomplished despite an accelerated construction schedule, and despite mixing and placing the material in the field under varied environmental conditions.
The effects of message threat/reflection on psychological reactance in traffic safety messaging
(Montana State University - Bozeman, College of Engineering, 2020) Townsend, Asher Campbell; Chairperson, Graduate Committee: Nicholas Ward
Psychological reactance is a motivation to regain a freedom after it has been lost or threatened, which has led people to largely resist the social influence of others (Steindl et al., 2015). Steindl et al. (2015, pg. 205) also define psychological reactance as 'an unpleasant motivational arousal that emerges when people experience a threat to or loss of their free behaviors.' Seat belt use and distracted driving are two of the highest-fatality behaviors and they pose the greatest threat to other drivers' health and safety on U.S. roadways (NHTSA, 2018a). The purpose of this research is to investigate whether psychological reactance may be a significant factor in influencing people's reactions and their choices to continually engage in risky behaviors. Moreover, this research looks at whether select individuals are more prone to experiencing reactance and how it may influence their willingness to follow driver safety messaging. Specifically, this research will investigate whether varying message threat and message reflection influence the amount of reactance experienced. Three main components of psychological reactance are of concern in the study: Reactance Attitude, Emotional Reactance, and Threat to Freedom. Each of these behaviors is measured for varying message conditions for two different message sets: one for Seat Belt Use and another for Distracted Driving. For the Emotional Reactance and Threat to Freedom reactance measures, there is a significant correlation between the measures and reactance proneness. It was found that as proneness increases, the resulting psychological reactance increases as well. For the Distracted Driving messages, there was a significant effect of Message Threat for the Emotional Reactance and Threat to Freedom conditions such that low threat messages elicited less psychological reactance than high threat messages. From this study, we recommend the following aspects for designing traffic safety messages: 1) Messages should use non-controlling language (consider, can, could, may, try) over controlling language (should, ought, must, need), 2) Messages should aim to be suggesting (try to do this), rather than commanding (you MUST do this!). Additionally, high threat messages may tend to elicit stronger reactance independent of reactance proneness, supporting the proposal of avoiding high threat messages for traffic safety.
An investigation modeling risk of wildlife-vehicle collisions in Montana, USA
(Montana State University - Bozeman, College of Engineering, 2019) Bell, Matthew Andrew; Chairperson, Graduate Committee: Yiyi Wang and Damon Fick (co-chair)
Road ecologists and transportation engineers have been exploring new methods to adapt to the environmental and motorist safety concerns involving wildlife-vehicle collisions. There are over one-million crashes with large-bodied wildlife every year in the U.S. that result in substantial property damage and personal injuries. Recent studies modeling these collisions identify where they cluster, and the landscape, road, and driver characteristics that influence the likelihood of a collision along short road corridors and small geographic regions. This research expands on current knowledge and attempts to model the risk of wildlife-vehicle collisions on a large geographic scale. This research investigates different analysis methods and creates predictive models that will estimate the risk of a wildlife-vehicle collision as drivers travel across multiple ecosystems. Different analysis units were created to extract two similar datasets that are modeled against two different response variables -- reported collisions and roadkill locations. Regularization is used to help with feature selection. Negative binomial regression models are built to predict risk. Random forest machine learning helps better understand the percent of variance explained by the variables in each model. A range of statistical measurements were taken to compare the non-nested models. The best performing model is applied to the seasonal division of data. Yearlong and seasonal risk is mapped onto the road network and color-coded to show the differences in risk on Montana's road network. The maps capture the changes in risk throughout the year, they generally match where wildlife-vehicle collisions actually happen, and even coincides with published work on the locations of collision hotspots in Montana. This research is the basis for future complex real-time risk-mapping models that can be integrated into smart technology and developed into on-board driver alert systems. With the advancements of autonomous vehicle, it is possible to incorporate real-time driving data into models that will analyze wildlife-vehicle collision risk based on vehicle location, season, time of day and driving habits. This can increase driver safety by informing them when they are traveling in areas where wildlife-vehicle collisions are more likely to happen, and can be especially helpful while driving on unfamiliar roads.
Feasibility of non-proprietary ultra-high performance concrete (UHPC) for use in highway bridges in Montana: phase II field application
(Montana State University - Bozeman, College of Engineering, 2020) Scherr, Riley James; Chairperson, Graduate Committee: Michael Berry
Ultra-high performance concrete (UHPC) has properties far exceeding those of conventional concrete. The MDT Bridge Bureau is interested in using UHPC in field-cast joints between precast concrete deck panels. The primary objective of the research discussed herein was to further investigate and develop a non-proprietary UHPC mix developed for use in Montana. Specifically, this research (1) investigated the potential variability in concrete performance related to differences in constituent materials, (2) investigated issues related to the field batching/mixing of the these UHPC mixes, and (3) tested rebar bond strength and its effects on requisite development lengths. Throughout this research project, the different aspects used to test the UHPC performance and prepare the UHPC, further detailed in chapter 3 of this report, are mixing procedures, flow testing, specimen casting, preparation and curing procedures, compression testing, flexure testing, set time estimates, and bond strength/pullout capacity testing. Variations in the source of the constituent materials had fairly minor effect on UHPC performance. Flow generally increased with increasing aggregate moisture content, and the 7- and 28-day compressive strengths generally decreased. Adjusting the mix water to account for the varying aggregate moisture contents did not have a significant effect on flow, but it was observed to slightly increase the compressive strengths in many cases. The UHPC mixes obtained strengths exceeding 10 ksi in the first 24 hours and continued to gain strength over the duration of testing, ultimately reaching strengths of around 20 ksi at 182 days. Batch size did not have a significant effect on flow or compressive strength; however, larger scale mixes required 10% more water and HRWR in order to obtain the same performance when size was increased from 0.2 cu. ft. to 2.5 cu. ft. or larger. Flow was observed to decrease with increasing temperature, while the compressive strengths for the hottest mix were consistently the lowest. The reinforcement that met the minimum FHWA recommendations all reached maximum applied pullout stresses above the rebar yield strengths. This indicates that the FHWA embedment depth recommendations should be suitable for use in the purposed bridge closure pours with this research's developed UHPC mix.
An investigation of operational performance on two-lane highways
(Montana State University - Bozeman, College of Engineering, 2018) Jafari, Amirhossein; Chairperson, Graduate Committee: Ahmed Al-Kaisy
A high percentage of the US road networks are two-lane highways. The Highway Capacity Manual (HCM) is the standard reference used in the US for traffic analysis of such highways (HCM 2016). This manual uses a qualitative measure called 'Level of Service (LOS)' to show the quality of traffic flow on the highway network. Performance measures are used as indicators of the LOS in the HCM. The current manual uses Average Travel Speed (ATS), Percent Time Spent Following (PTSF), and Percent Free Flow Speed (PFFS) for measuring LOS on two-lane highways. However, several studies reported that the HCM methodology falls short in several aspects including the performance measure used for operational analysis on two-lane highways. Moreover, the current guidelines of the HCM regarding passing lanes are very limited and based on studies conducted more than three decades ago (Harwood and St. John 1985, 1986). Constructing a passing lane is expensive and there is a need to use accurate methods for the design of such facilities. Therefore, the goal of this study is to examine new performance measures for operational analyses of two-lane highways as well as developing new guidelines for the design of passing lanes. Multiple investigations were conducted using field data from four states in the US as well as microscopic traffic simulation software, SwashSim. Using field data and statistical analysis as well as the results of a survey, the most appropriate performance measures were selected. Additionally, traffic simulation software was used to investigate the operational improvement of passing lanes. Optimum length and effective length of passing lanes were investigated. Optimum length has been used to refer to the length that would bring most operational benefits given the amount of passing lane investments while effective length is defined as the length of two-lane highway over which the effect of a passing lane extends. Moreover, the operational efficiency of different passing lane design configurations were examined to identify the most appropriate length and spacing to be used in the planning and design of passing lanes. In addition, the operational performance of 2+1 roads was investigated in this study and some guidelines for design of these facilities are provided. 2+ 1 highways have one lane in each direction of travel and the middle lane alternates between the two directions.
Vehicles, grooming, and other factors affecting snowroad longevity in Yellowstone National Park
(Montana State University - Bozeman, College of Engineering, 2018) Nelson, Molly McKellar; Chairperson, Graduate Committee: Edward E. Adams
In winter, the National Park Service (NPS) at Yellowstone grooms snow that builds up on the park roads, making 'snowroads' passable by snowmobiles and snowcoaches. The NPS has recently allowed experimental snowcoaches on low-pressure tires (LPTs) in addition to traditional tracks. As they consider a permanent policy on these LPTS, they want to understand these vehicles' impacts on snowroads compared with those of traditional tracked vehicles and snowmobiles. They also want to know how to optimize other operations (e.g., grooming) to maintain quality roads that support safe travel through the park. This two-year field study investigated the snowroad quality in the park and factors influencing this quality. The approach involved data collection on both parkwide road conditions and individual vehicle passes. Both controllable and non-controllable factors were considered to provide information on their relative influence. Parkwide road quality analysis involved collecting GPS data on grooming activity, weather data from existing stations, road depth through radar measurements, traffic counts from motion-sensor cameras, hardness data, and snow sample analysis. The vehicle-by-vehicle impact study involved both subsurface and surface measurements in the road. Load cells, accelerometers, a high-speed, high-definition camera, a penetrometer, and a 'profilometer' provided measurements. Data analysis combined with existing literature provided insights into best practices for the NPS. Parkwide, snowroads harden throughout the season, with temperatures and traffic load being contributing factors. Grooming results in a harder road if snow disaggregation is followed by compaction, and with a longer set time between grooming and traffic. Individual vehicles' impacts are driven by surface interaction rather than motion at depth in the snowroad. On hard, groomed snowroads, both tracked and LPT snowcoaches can form ruts, but tracked vehicles continue to dig ruts deeper whereas LPT coaches' ruts level out and stop deepening with subsequent passes. This seems to be because LPTs form ruts primarily through compaction and tracked vehicles through snow displacement. Reduced tire pressures reduce rut formation and can harden the road. Results from this study demonstrate that LPT coaches should not be disallowed from Yellowstone based on road impacts. Other results will inform NPS operations to optimize grooming practices.
A Yellowstone snowroad rutting investigation: a comparison of tracks vs. tires and other contributing factors
(Montana State University - Bozeman, College of Engineering, 2018) Phipps, Ry Edward; Chairperson, Graduate Committee: Daniel Miller
Yellowstone National Park (YNP) has been experiencing more snowroad rutting in the last ten years. Additionally, YNP has recently (winter 2013 -2014) been experimenting with permitting large low-pressure tire vehicles to operate on the parks' snowroads. To gain a better understanding of snowroad degradation, YNP employed a team of snow scientists from Montana State University. In the winter of 2015, a large scale, two year, snowroad rutting study began in YNP. Parameters pertaining to snowroad strength and the difference in impact to the snowroads between tracked and wheeled vehicles were examined. This thesis in addition to Nelson's (2018) thesis produce a detailed overview of controllable and uncontrollable factors of maintaining and measuring impacts to the snowroads of Yellowstone National Park. Instruments were developed to collect data in the field and in the Sub-Zero Lab at Montana State University. These instruments allowed researchers to quantify crucial differences between vehicle types and the behaviors associated with them. Once data was collected, the data was post-processed in various ways to analyze trends pertaining to snowroad strength and degradation. With the data processed and analyzed, the profilometer and hardness data proved to be the most informative on snowroad degradation tendencies, however, the other instruments helped reinforce conclusions made with the hardness and profilometer data. The process of taking subsurface measurements on vehicle pass-bys, allowed researchers to confirm that rutting is most closely tied to vehicle-surface interactions (~ top 10 cms). It was determined that wheeled and tracked coaches can both cause ruts but by different processes. Wheeled vehicles are primarily causing ruts through compaction whereas tracked vehicles primarily cause ruts through a process of snow displacement. Ruts form from wheeled coaches but after subsequent passes the cross-sectional area of the rut tends to level off, especially when inflation pressure is decreased. While tracked vehicles' ruts continue to grow in size after subsequent passes. Additionally, snowroad hardness was affected differently between tracks and tires. Tracks and tires at higher pressures (> or = 62 kPa) tended to more often soften the snowroad, whereas lower pressure tires (< 62 kPa) tended to harden the snowroad.
The influence of mine reclamation and highway reconstruction activities on grizzly bear habitat selection in the Cooke City basin, Montana
(Montana State University - Bozeman, College of Agriculture, 2016) Rossi, Joao Luiz; Chairperson, Graduate Committee: Bok Sowell
The grizzly bear (Ursus arctos) population of the Greater Yellowstone Ecosystem is increasing in numbers and expanding its range. In this scenario, the number of conflicts between humans and grizzly bears is likely to increase. Understanding how grizzly bear habitat selection is affected by concentrated high human use, such as construction projects, plays a major role in management decisions for this species. In this research, we combined bear sign data collected in 27 permanent transects during 11 years (1990-91, 1996-97, 2003-04, and 2007-11) with food habits analysis to provide a description of grizzly bear habitat use in 91km 2 of the Cooke City Basin, Montana. Data were collected during years of mine reclamation (2003-04), highway reconstruction (2007-09), and years when no major human activities occurred (1990-91, 1996-97, and 2010-11). The main objectives of this study were to quantify grizzly bear spatial avoidance to mine reclamation and highway reconstruction activities and provide knowledge about environmental factors influencing grizzly bear habitat in the Basin. Resource selection functions were used to address these goals. Results showed that, in the Cooke City Basin, grizzly bears selected for mid-high elevation, forested, south-west facing slopes (areas where whitebark pine seeds are most abundant) and avoided areas of high tertiary road density. Mine reclamation occurred near whitebark pine forests. The estimated grizzly bear use of areas within 1 km and 2 km of reclamation epicenters decreased 83% and 52%, respectively, in years of mine reclamation. Grizzly bears did not avoid areas beyond 2 km of mine reclamation or areas within 4 km of highway reconstruction in years when these activities occurred. The lack of avoidance associated with highway reconstruction is likely explained by the fact that this occurred in the lowest elevation areas (below 2500 m) that are used less by grizzly bears. Grizzly bears use in the Cooke City Basin were mostly uninterrupted by two major construction projects. However, temporary and localized habitat loss occurred when construction was focused near whitebark forests with high bear use. Temporary habitat loss was not observed when construction occurred in areas distant from whitebark forests and used less by bears.
Privatization and state transportation services : a qualitative study
(Montana State University - Bozeman, College of Business, 2000) Nopper, Marie; Chairperson, Graduate Committee: Norman L. Millikin
The major purpose of this paper was to interview and report the attitudes of individuals who are currently involved with highway transportation in the State of Montana regarding privatization of certain Montana Department of Transportation duties or services. The in-depth interviews explored the topic of privatization and individual opinions on the reliance on private enterprise, market forces and competition for providing public services. Personal interviews were conducted with thirteen carefully selected individuals. At the time of the interviews, each individual was involved in one of four areas of highway transportation; one, private sector engineering or consultant design, including consulting, road design, bridge design or traffic design. Two, current or past employees of the Montana Department of Transportation in the areas administration, maintenance or engineering. Three, general contractor representation; and four, relevant transportation experience through a higher education institute. Preparation for the interviews was based upon a substantial review of literature, including privatization plans from the Commonwealth's of Virginia and Massachusetts, as well as the states of Idaho, Washington, Oregon and Iowa. Privatization plans written by the Montana Contractors' Association, the Providence of Alberta, Canada, the City of Great Falls, Montana, and private organizations such as the Reason Foundation were also reviewed. In addition, related materials from the Providence of British Columbia, Canada, the U.S. Department of Transportation, the U.S. Department of Labor, the State of Kansas and numerous reports from private consulting firms were reviewed. The main conclusions of these interviews are: (I) There is no one specific definition of the term privatization. (2) There is no clear indication financial savings would occur if the overall mix changed. (3) There would be no savings from any change in the public and private sector mix with regard to buildings, equipment or land. Moving personnel or labor more toward private sector may be a short-term cost saving, but long-term savings are unclear. (4) MDT should be responsible for determining the increase, decrease or maintaining the level of privatization. (5) There is significant room for improvement in oversight of some of the privatization areas. (6) There is a great deal of confusion over how MDT evaluates the success or failure of privatization or private sector performed services or projects. (7) There is a high level of satisfaction with the current mix of private and public sector work with regard to privatization. The recommendations based upon this study are: (1) Maintain the current mix of contracting out or outsourcing for the areas of construction and maintenance. MDT should investigate increasing the amount of outsourcing and re-direct MDT design as project review and oversight for possible improved performance in the area of consultant design. (2) Additional educational and training opportunities should be investigated. (3) MDT should determine levels of privatization without being encumbered by political forces, either internal or external. (4) MDT needs clearer and more communication, both internally and externally, describing the processes of oversight of projects.
Intelligent countermeasures in ungulate-vehicle collision mitigation
(Montana State University - Bozeman, 2002) Farrell, Justin Edward; Chairperson, Graduate Committee: Lynn R. Irby

Theses and Dissertations at Montana State University (MSU)

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