• Laboratory and Field Evaluation of Modified Asphalt Binders and Mixes for Alaskan Pavements

      Liu, Jenny; Liu, Jun (2019-08)
      In order to properly characterize modified asphalt binders and mixes for Alaskan pavements, this study evaluated properties of 13 asphalt binders typically used in Alaska from three different suppliers, and 10 hot mix asphalt (HMA) mixtures which were either produced in the lab or collected from existing paving projects in Alaska. Various binder and mixture engineering properties were determined, including true high binder grades, complex modulus (G*), and phase angle (δ) at high performance temperatures, multiple stress creep recovery rate and compliance, bending beam rheometer stiffness and m-value, Glover-Rowe parameter, ΔT, rheological index, and crossover frequency for binders, and rut depth, critical strain energy release rate (Jc), Indirect tensile (IDT) creep stiffness and strength for mixtures. Binder cracking temperatures were determined using asphalt binder cracking device. Mixture cracking temperatures were determined with IDT creep compliance and strength data. It was found that rutting and cracking resistances of the mixtures with highly modified binders were better than the mixture with unmodified asphalt binder (PG 52-28). Future recommendations for highly modified asphalt binders applications and research were provided based on laboratory testing results and field survey evaluation.
    • Long-term Stabilization of Disturbed Slopes Resulting from Construction Operations

      Perkins, Robert (Center for Environmentally Sustainable Transportation in Cold Climates, 2018-03)
      Highway construction disturbs soil, which must be stabilized to prevent migration of soil particles into water bodies. Stabilization is enforced by law, regulation, and a permit system. Stabilization is most efficiently attained by reestablishment of vegetation, and permits sometimes specify this method of stabilization. Revegetation is difficult in northern Alaska, and seeded grasses often die in a year or two, while reestablishment with native vegetation takes several years. A literature search and interviews with experts indicates that simply extending this “establishment period” has many practical difficulties. Field investigations and interviews indicate that in northern Alaska little erosion occurs at slopes with failed vegetation, which implies that vegetation was not critical to reducing contamination and the expense of revegetation was unnecessary. However, when revegetation is specified in standard permit language, and contractor, owner, and regulator must close out projects, grasses are utilized. This research supports the recommendation that the Alaska Department of Transportation and Public Facilities work with the Alaska Department of Natural Resources and the Alaska Department of Environmental Conservation to develop special standards for projects north of the Brooks Range and between the Brooks and Alaska ranges, that recognize the low erosion potential of clean road fill – embankments.
    • Mapping the Wolverine Way: Identifying Conservation Corridors and Transboundary Linkages in the Canadian Crown of the Continent Region

      Clevenger, Anthony P. (2019-09-13)
      The Canadian Crown of the Continent (CCoC) is one of three zones where wolverines can move between Canada and the US, providing the last links for recruitment and ultimately gene flow to the highly fragmented population in the US Rocky Mountains. However, a combination of rapidly expanding logging, energy development and motorized recreation, along with a growing road network, threatens to fragment and diminish connections in this critical transboundary linkage between the US and Canada. This report summarizes a project to complete a 3-year sampling effort in the CCoC, which in turn completed a larger 6-year effort over a vast area of the central and southern Canadian Rockies. In 2016, the research team surveyed the last unsampled portion of the Alberta Rockies (south of Kananaskis Country to Highway 3) in addition to a substantial portion of the East Kootenay region of the British Columbia Rockies (BC; >9000 km2). This follow-up effort allowed the team to complete an entire ecoregion-wide wolverine survey in the Canadian Rockies ecoregion, from the US-Canadian border north to Banff and Yoho National Parks. From this data, researchers created density estimates and occupancy models of wolverine distribution and its multiple landscape stressors across an extensive and complex region of the Great Northern Landscape. The report summarizes research findings and makes recommendations regarding management strategies.
    • Modeling Impacts of Cold Climates on Vehicle Emissions

      Chung, Serena (Center for Environmentally Sustainable Transportation in Cold Climates, 2017-01-20)
      This project relates to the research thrust area of ‘environmental impact assessment,' specifically the impact of cold climates on vehicle exhaust emissions. Motor vehicles emit pollutants that are harmful to human. Emissions are thought to be elevated during engine cold starts. During winter, low-lying temperature inversion can trap vehicle emissions near the surface, leading to significantly elevated pollutant concentrations. Despite the importance, vehicle emissions data for cold climates are sparse and the accuracy of vehicle emissions model parameterizations for cold climates is not known. The goal of this project is to improve ability of EPA's Motor Vehicle Emission Simulator (MOVES) model to simulate cold start emissions in cold climates
    • Monitoring Winter Flow Conditions on the Ivishak River, Alaska

      Toniolo, Horacio; Vas, D.; Keech, J.; Bailey, J. (Center for Environmentally Sustainable Transportation in Cold Climates, 2017-09)
      The Sagavanirktok River, a braided river on the Alaska North Slope, flows adjacent to the trans-Alaska pipeline for approximately 100 miles south of Prudhoe Bay. During an unprecedented flooding event in mid-May 2015, the pipeline was exposed in an area located approximately 20 miles south of Prudhoe Bay. The Ivishak River is a main tributary of the Sagavanirktok River, but little is known about its water flow characteristics and contribution to the Sagavanirktok River, especially in winter and during spring breakup. To gather this information, we installed water level sensors on two main tributaries of the Ivishak River (Upper Ivishak and Saviukviayak rivers), early in winter season 2016–2017, in open-water channels that showed promise as locations for long-term gauging stations. Our ultimate goal was to find a location for permanent deployment of water level sensors. By February, the first sites chosen were ice covered, so two additional sensors, one on each river, were deployed in different locations. Some of the sensors were lost (i.e., carried away by the current or buried under a thick layer of sediments). Water level data gathered from the sensors showed a maximum change of 1.07 m. Winter discharge measurements indicate a 44% reduction between February and April 2017. A summer discharge measurement shows a 430% increase from winter to summer.
    • Near-Roadway Air Pollution: Evaluation of Fine Particulate Matter (PM2.5) and Ultrafine Particulate Matter (PM0.1) in Interior Alaska

      Aggarwal, Srijan; Kadir, Abdul; Belz, Nathan (2019-01-28)
      This report presents a study of fine (PM2.5) and ultrafine (PM0.1) particles in the Fairbanks North Star Borough (FNSB) in Interior Alaska, with specific emphasis on the relationship of ultrafine particles (UFPs) to vehicular traffic. Chapter 1 provides a summary of published literature on particulates in air from vehicular emissions. Chapter 2 provides a novel and robust GIS-based data analysis approach to PM2.5 data collected by the FNSB. This analysis approach is convenient for identifying hotspots, as well as locations where PM2.5 changes either abruptly or continuously or does not change at all. The results reveal that average on-roadway PM2.5 concentrations are higher in North Pole than in Fairbanks, and mean levels are higher in stationary background monitoring data than in mobile monitoring on-roadway data. Not surprisingly, significant negative correlations were found between temperature and PM2.5. Chapter 3 presents the results from the data collection campaign to measure UFPs at roadside locations in Fairbanks and North Pole and investigate the relationship of UFPs with traffic and meteorological parameters. Multilinear predictive models were developed for estimation of UFPs and PM2.5 based on weather and traffic parameters. Overall, this study improves our understanding of on- and near-roadway particulates in a cold-climate region.
    • A New Sustainable Additive for Anti-Icing Pavement

      Zhang, Yan; Shi, Xianming (2019-08-30)
      Based on a review and synthesis of the state-of-the-art literature on asphalt pavement with anti-icing additives, this laboratory study developed an anti-icing asphalt pavement that incorporates innovative salt-storage additives with a sustained salt-release rate. These additives were prepared through a surface treatment approach, in which zeolite containing CaCl2 was coated by a porous epoxy layer. The anti-icing performances and mechanical properties of asphalt mixture with the obtained additives were investigated. The experimental results indicated that the anti-icing capability of asphalt mixture at both -3.9 °C (25°F) and -9.4 °C (15°F) was significantly improved by the addition of the additives, and the friction coefficient of the pavement at 60 min after moisture spray was 0.75 at -3.9 °C to 0.55 at -9.4 °C. Reducing the size of additives resulted in a further improved anti-icing capability. Under simulated conditions, the estimated effective anti-icing period of asphalt pavement with additives #8, #16, and #30 were 5.8 years, 9.9 years and 15.3 years, respectively. The incorporation of the additives exhibited negligible effect on the moisture damage resistance of asphalt mixture, and almost all the mixtures passed the WSDOT specification as well as the Wisconsin and Iowa specifications. The rutting resistance, mid-temperature (fatigue) cracking resistance, and low-temperature (thermal) cracking resistance of asphalt mixture improved due to the addition of these anti-icing additives to various extents.
    • A Novel Systematic Strategy Towards Air-Purifying, Corrosion Resistant and Self-Healing Concrete Infrastructure

      Yang, Zhengxian (2019-09-15)
      Transportation causes major emissions of harmful gases (NOx, CO, VOCs). These pollutants also travel long distances to produce secondary pollution such as acid rain. The most popularly used photocatalytic cementitious composites based on TiO2 achieve the air purification function under ultraviolet sunlight, significantly impeding a broader application of photocatalytic cementitious composites. This study focused on developing an environmentally friendly and durable cementitious system based on the multifunctional photocatalytic Graphitic carbon nitride (g-C3N4). The photocatalytic cementitious composites (PCC) were prepared in three manners: (1) incorporating g-C3N4 nanosheets (CNNs) in cement at three mixing dosages (0.5%, 1% and 2% by weight of cement), (2) applying CNNs at various concentration levels as the coating on recycled asphalt pavement aggregate, (3) applying CCNs s with vinyl chloride/vinyl ester/ethylene copolymer (as a binder) as the coating on cement mortar. The photocatalytic performance and durability of the newly developed cementitious composites were evaluated systematically and the results showed that the PCC hold marked efficiency in terms of NOx removal and self-cleaning when the CNNs were applied in a proper way. The obtained knowledge sheds light on a future perspective of developing a novel systematic strategy towards air-purifying, corrosion resistant, and self-healing concrete infrastructure.
    • Numerical Simulation of Snow Deposition Around living Snow Fences

      Petrie, John; Zhang, Kun; Shehata, Mahmoud (2019-09-13)
      In this study, computational fluid dynamics (CFD) was used to investigate the air flow around porous snow fences to gain insight into snow transport and deposition in the vicinity of fences. Numerical simulations were performed to validate the CFD approach using experimental data from a wind tunnel study. Subsequent simulations were used to test the use of a porosity model to represent fence geometry and determine the effect of fence spacing for fences comprised of multiple rows. The results demonstrate that CFD simulations can reproduce the aerodynamics around porous fences. Additionally, the flow field generated with a porosity model is in close agreement with that from a model with explicit representation of fence porosity. Simulations of fences comprised of two rows spaced at various distances demonstrate that when the row spacing is small the fence behaves as a single row.
    • Performance of TenCate Paving Interlayers in Asphalt Concrete Pavements

      Liu, Jenny; Zhao, Sheng; Li, Lin (Center for Environmentally Sustainable Transportation in Cold Climates, 2017-08)
      As a continued effort of a previously completed project entitled “Performance of TenCate Mirafi PGM-G4 Interlayer-Reinforced Asphalt Pavements in Alaska,” this project evaluated two newly modified paving interlayers (TruPave and Mirapave) through overlay, dynamic modulus tests and low-temperature performance tests. A field survey was conducted to further evaluate the performance of three paving interlayers (G4, G50/50, and G100/100) applied to field sections constructed in May 2013 at Milepost 148–156 Richardson Highway in Alaska. Overlay test results indicate that asphalt concrete (AC) with paving interlayers (TruPave and Mirapave) shows lower reduction in peak load, suggesting better cracking resistance. The dynamic modulus measurement of AC with paving interlayers reveals more rational results from the IDT mode test than the AMPT method due to similar stress conditions in the paving interlayer. With paving interlayers, the temperature sensitivity and cracking potential of AC material were reduced according to the results from the IDT creep test. Field survey results confirm that all sections reinforced with paving interlayers (G4, G50/50, and G100/100) had better cracking resistance than the control section.
    • Pre-Stress Loss Due to Creep in Precast Concrete Decked Bulb-Tee Girders Under Cold Climate Conditions

      Vandermeer, Drew; Ahn, Il-Sang (2019-07-31)
      Accurate estimation of pre-stress losses is one of the important issues for the design of precast, pre-stressed concrete bridge girders. While this subject has been long studied by many researchers, studies on pre-stress losses in cold climates are minimal. In the present research, long-term pre-stress loss due to concrete creep was studied based on concrete creep test. Two concrete creep test frames were fabricated and placed indoors and outdoors. Concrete strains were measured by Demountable Mechanical Strain Gauge (DEMEC) from two 612 high-strength concrete cylinders in each frame. The concrete strains were collected for 11 months (7/26/2017 – 6/21/2018) after loading, and outdoor ambient temperature dropped below 0C between 100 and 250 days. Between 50 and 100 days, two curves from the two frames are similar in their patterns and values. After 100 days, the total strain from the indoor frame slowly increased reaching 1,600 and 1,700 after 250 days. However, the total strain from the outdoor frame varied between 1,000 and 1,500 and the averaged total strain was 1,300 after 250 days. In cold temperature, the occurrence of concrete creep and shrinkage was suppressed.
    • Prediction of Thermal Behavior of Pervious Concrete Pavements in Winter

      Chen, Zhao; Nantasai, Benjamin; Nassiri, Somayeh; Haselbach, Liv (Center for Environmentally Sustainable Transportation in Cold Climates, 2017-05-15)
      Because application of pervious concrete pavement (PCPs) has extended to cold-climate regions of the United States, the safety and mobility of PCP installations during the winter season need to be maintained. Timely application of salt, anti-icing, and deicing agents for ice/snow control is most effective in providing sufficient surface friction when done at a suitable pavement surface temperature. The aim of this project was to determine the thermal properties of PCP during the winter season, and to develop a theoretical model to predict PCP surface temperature. The project included a laboratory and a field component. In the laboratory, thermal conductivity of pervious concrete was determined. A linear relationship was established between thermal conductivity and porosity for pervious concrete specimens. In the field, the pavement temperature in a PCP sidewalk installation at Washington State University was monitored via in-pavement instrumentation. Based on the field data, the Enhanced Integrated Climatic Model (EICM) was developed and validated for the site, using PCP thermal properties and local climatic data. The EICM-predicted PCP surface temperature during the winter season agreed well with the field temperature. Overall, the predicted number of days that the pavement surface fell below 32°F agreed well with the number based on field data for 85% of the days. Therefore, the developed model is useful in identifying those days to apply deicer agents. Finally, a regression model using climatic indices was developed for PCP surface temperature prediction in the absence of a more advanced temperature model.
    • Recent Advances in Sustainable Winter Road Operations – A Book Proposal

      Shi, Xianming (Center for Environmentally Sustainable Transportation in Cold Climates, 2017-08)
      Investing in winter transportation operations is essential and beneficial to the public and the economy. The U.S. economy cannot afford the cost of shutting down highways, airports, etc., during winter weather. In the northern U.S. and other cold-climate areas, winter maintenance operations are essential to ensure the safety, mobility, and productivity of transportation systems. Agencies are continually challenged to provide a high level of service and improve safety and mobility in a fiscally and environmentally responsible manner. To this end, it is desirable to use the most recent advances in the application of materials, practices, equipment, and other technologies. Such best practices are expected to improve the effectiveness and efficiency of winter operations, to optimize material usage, and to reduce associated annual spending, corrosion, and environmental impacts. Currently, no professional societies, scientific journals, or textbooks are dedicated solely to sustainable winter road operations, and key information is scattered across a variety of disciplines. The objective of the proposed book is to summarize the best practices and recent advances in sustainable winter road operations for the purposes of education and workforce development. This book is now in press and can be cited as follows: Shi, X., Fu, L. (2017). Sustainable Winter Road Operations (Eds.). ISBN: 978-1-119-18506-2. Wiley-Blackwell.
    • Recycled Glass Fiber Reinforced Polymer Composites Incorporated in Mortar for Improved Mechanical Performance

      Rodin, Harry; Nassiri, Somayeh; Englund, Karl; Fakron, Osama; Li, Hui (Center for Environmentally Sustainable Transportation in Cold Climates, 2017-12)
      Glass fiber reinforced polymer (GFRP) recycled from retired wind turbines was implemented in mortar as a volumetric replacement of sand during the two phases of this study. In Phase I, the mechanically refined GFRP particle sizes were sieved for four size groups to find the optimum size. In Phase II, the select GFRP size group was incorporated at three different volumetric replacements of sand to identify the optimum replacement content. The mixtures were tested for compressive strength, flexural strength, toughness, and the potential for alkali-silicate reaction. Incorporation of GFRP in mortar proves promising in improving flexural strength and toughness in fiber-like shapes and 1–3% volumetric fractions.
    • The Reliability and Effectiveness of a Radar-Based Animal Detection System

      Huijser, Marcel P.; Fairbank, Elizabeth R.; Abra, Fernanda D. (Center for Environmentally Sustainable Transportation in Cold Climates, 2017-09)
      This document contains data on the reliability and effectiveness of an animal detection system along U.S. Hwy 95 near Bonners Ferry, Idaho. The system uses a Doppler radar to detect large mammals (e.g., deer and elk) when they approach the highway. The system met most of the suggested minimum norms for reliability. The total time the warning signs were activated was at most 90 seconds per hour, and likely substantially less. Animal detection systems are designed to detect an approaching animal. After an animal has been detected, warning signs are activated which allow drivers to respond. Results showed that 58.1–67.9% of deer were detected sufficiently early for northbound drivers, and 70.4–85% of deer were detected sufficiently early for southbound drivers. The effect of the activated warning signs on vehicle speed was greatest when road conditions were challenging (e.g., freezing temperatures and snow- and ice-covered road surface) and when visibility was low (night). In summer, there was no measurable benefit of activated warning signs, at least not as far as vehicle speed is concerned. Depending on the conditions in autumn and winter, the activated warning signs resulted in a speed reduction of 0.69 to 4.43 miles per hour. The report includes practical recommendations for operation and maintenance of the system and suggestions for potential future research.
    • SIZING HYDRAULIC STRUCTURES IN COLD REGIONS TO BALANCE FISH PASSAGE, STREAM FUNCTION, AND OPERATION AND MAINTENANCE COST

      Blank, Matt; Dockery, David; Pohl, Christina (2019-03)
      The purpose of this research was to evaluate how characteristics of hydraulic structures, such as slope or size, used at crossings over waterways relate to operation and maintenance (O&M) effort, fish passage, and stream function. Data on O&M concerns, fish passage concerns, and crossing characteristics were collected from 45 road-stream crossings in Prudhoe Bay, Alaska, during lower and higher water periods in both 2014 and 2015 (four events total). Logistic regression and generalized mixed models were used to examine relationships between O&M effort (response) and five explanatory variables. For all data from all years combined, there were no observable associations among O&M and culvert type or constriction ratio. However, lower constriction ratios were observed for sites with O&M needs in the June 2014 data set. The proportion of sites with both fish passage and O&M concerns was 0.52; comparatively, the proportion of sites with no fish passage concern but with O&M concern was 0.35.
    • Stormwater-Pavement Interface in Cold Climates

      Haselbach, Liv; Nassiri, Somayeh (Center for Environmentally Sustainable Transportation in Cold Climates, 2017-05-27)
      This project relates to “managing stormwater runoff in cold climates” and addresses the feasibility of low-impact development at a regional demonstration site in eastern Washington. The studies relate to seven large permeable pavement systems. The findings for similar climates and soils are as follows:  The draindown times for retention in Palouse or similar clay soils may handle many typical storms.  On average, every square foot of a permeable pavement system installed also receives run-on from another square foot of impermeable pavement, doubling its impact on both stormwater quantity reduction and stormwater quality improvement.  Most of the clogged sections on various applications were downslope of other areas.  Permeable pavements installed in areas targeted for additional stormwater quantity control and quality improvement may be feasible.  On average, the cleaning for installations is less frequent than annually. Power washing plus vacuuming appears to be an effective method for pervious concrete.  Surface distress was usually where vehicles turned, or from placement activities.  Preliminary studies on various surface treatments on pervious concrete show promise for added safety benefits under wintry conditions.  Both detention-type and retention-type permeable pavement systems appear to have little negative impact on neighboring soils in the winter under the study conditions. However, further research is needed for different designs of retention-type systems to ensure that water volumes in the aggregate storage bed do not allow for sufficient water flow into neighboring soils that might result in ice lens formation or other negative impacts.
    • Sustainable Construction in Remote Cold Regions

      Perkins, Robert (Center for Environmentally Sustainable Transportation in Cold Climates, 2015-12-31)
      The goal of this project was to identify sustainable construction techniques appropriate for remote and cold regions, some of which apply to operations and maintenance as well. The vast body of literature regarding green construction in warm regions was reviewed, and information that might be applicable to cold and remote regions was ascertained. A hierarchal taxonomy was developed to categorize the information and reduce it to a form useful for presentation to engineering and construction managers. Twenty-two engineers and construction managers, all familiar with cold regions and remote projects, were interviewed, and the information and taxonomy were reviewed with them. This process resulted in a set of preliminary guidelines, which were then presented at two different meetings: one at AGC and one at the DOT, Central Region, where the preliminary guidelines were revised slightly. The final set of guidelines, approximately 160 suggestions and notes, was used to develop a module for UAF construction management classes, although it is suitable for other learning venues. The module, the Guidelines, as well as a preliminary paper are available on the CESTiCC website.
    • A Targeted Approach to High-Volume Fly Ash Concrete Pavement (Phase I)

      Du, Sen; Shi, Xianming (2018-12)
      Unlike the conventional method of admixing nanomaterials directly in fresh concrete mixture, a more targeted approach was explored. Specifically, nanomaterials were used to improve the interface between coarse aggregate and cement paste, by coating the coarse aggregate with cement paste that contained graphene oxide or nanosilica. Using coated coarse aggregates, the mechanical and transport properties of high-volume fly ash (HVFA) concrete were tested to evaluate the effect of nanomaterial coating on the interface transition zone of concrete. The compressive and splitting strengths of HVFA concrete at 3, 7, 14, and 28 days and the water sorptivity and chloride migration coefficient at 28 days were studied. Results show that nanomaterial-coated coarse aggregate can improve the transport properties of HVFA concrete by reducing permeability. However, no improvement was seen in the compressive and splitting strengths when incorporating coated coarse aggregate, compared with direct mixing of nanomaterials in fresh concrete. Resistance to freezing/thawing cycles and scanning electron microscope/energy dispersive X-ray spectroscopy of concrete samples were also investigated to obtain a more comprehensive and mechanistic understanding of nanomaterial coating.
    • Transportation Life Cycle Assessment Synthesis Phase II

      Center for Environmentally Sustainable Transportation in Cold Climates, 2018-04-24
      The Transportation Life Cycle Assessment (LCA) Synthesis includes an LCA Learning Module Series, case studies, and analytics on the use of the modules. The module series is a set of narrated slideshows on topics related to environmental LCA. Phase I produced 27 modules, and Phase II added 10 more. The modules are available for download on the Lamar CEE website https://www.lamar.edu/engineering/civil/faculty/haselbach/lca-modules.html and on the CESTiCC website http://cem.uaf.edu/cesticc/publications/lca.aspx. The modules are around 20 minutes long and may be used for various purposes such as for class lectures or part thereof, and for background learning in research or application. The modules are organized into four topical areas, each containing overview and detailed modules. The A and α groups cover the international standards that define environmental LCA. The B and β groups summarize some of the typical environmental impact categories in LCA. The G and γ groups include software tools for LCA. The T and τ groups focus on the growing field of transportation with respect to LCA, a complex area of importance. The analytics section provides data on downloads of the modules from the websites and summary survey results from course implementation.