• Parks Highway Load Restriction Study Field Data Analysis

      Raad, Luffi (1998-02)
      The loss of pavement strength during spring thaw could result in excessive road damage under applied traffic loads. Damage assessment associated with the critical thaw period is essential to evaluate current load restriction policies. The Alaska Department of Transportation and Public Facilities (AKDOT&PF) proposed a plan which will provide an engineering analysis fo field conditions with 100% loads on the Parks Highway for 1996. The study was jointly conducted by AKDOT&PF, the Alaskan Trucking Association (ATA), and the University of Alaska Fairbanks Institute of Northern Engineering Transportation Research Center (TRC). Extensive field data were collected and analyzed in an effort to monitor pavement damage during the spring of 1996 and determine the loss of pavement strength. The field data included: 1. Truck traffic data using the Chulitna weigh in motion (WIM) station and the scalehouses at Eagle River and Ester. WIM data were obtained for both northbound and southbound traffic from 199301996. Scalehouse data were obtained for Spring 1996 for comparison with WIM spring data. 2. Pavement temperature data (Spring 1996) for seven ground temperature sites representing typical conditions along the Parks Highway. 3. Profilometer data for pavement roughness and rutting obtained yearly (1993, 1995, and 1996) and also monitored over shorter intervals during Spring 1996. In addition, rut-bar measurements at selected points were also monitored during Spring 1996. 4. Falling Weight Deflectometer (FWD) data for both the northbound and southbound lanes for selected sections in lengths of eight 8 km (5 mile) along the Parks Highway. These data were used in backcalculation of pavement layer moduli, fatigue strength of the asphalt concrete surface, and corresponding damage factors resulting from spring-thaw weakening. Field data were used to analyze the damage effects on the Parks Highways. These included: analysis and comparison of WIM and scalehouse traffic data; determination of overweight axle loads and vehicles; comparison of north- and southbound traffic and its effect on pavement damage; analysis of ground temperature for thaw initiation and propagation; and simulation of the pavement's remaining life, with and without load restrictions, using mechanistic methods. This report presents results of these analyses.
    • Part-Load Economy of Diesel-Electric Generators

      Malosh, James B.; Johnson, Ronald (1985-06)
      Diesel-electric generators used to produce power in rural Alaska are often found to be inefficient and suffer from premature mechanical failures. Such failures are commonly caused by hydrocarbon build-up in the engine resulting from long-term operation under light-load conditions. There are several feasible approaches to this problem which use proven technology. The most technologically direct approach is to properly size systems. Another involves the optimum control of engine oil, coolant and intake air temperature with thermostatically-controlled electric heaters. Economic analysis shows that this approach could save as much as $13,000 per year in the cost of electricity for a 100 kw diesel generator operating at 25% load. However, further research is needed to establish that the mechanical problems associated with part-load operation are actually abated with proper control of operating temperatures. Practical experience implies that this should be the case. Acoustically tuned low restriction intake and exhaust systems are also an attractive approach because they provide a definite increase in efficiency under all operating conditions. However, these units must be developed for a specific engine and operating speed range. They are not presently commercially available, but could be developed in a continuing research effort. Parallel operation of small diesel-electric generators was suggested by many vendors and operators as a method of improving part-load performance. Though it has the benefit of redundant reliability, the economic analysis does not show a clear advantage because of higher electrical costs near full-load conditions. At very low loads, single small units may also suffer from the same mechanical problems as the large units. The other methods of improving part-load performance which include the use of improved injectors and microprocessor-controlled injection pumps are not presently feasible. However, the state of diesel engine technology is changing so rapidly that these items could become feasible in less than two years. These developments should be monitored closely.
    • Passive Solar Alaskan School

      Seifert, Richard D. (1984-12)
    • Passive Solar Heating in Alaska

      Zarling, John (1980-06)
      The relationship between the four elements of passive solar design for small buildings; south facing windows, thermal mass, thermal insulating shutters, and insulation thickness, were studied by computer simulation to determine their long-term effects on energy consumption. Solar and weather data for Fairbanks, Alaska, 65(degrees)N latitude, was the input to the TRNSYS Program used to perform the dynamic simulations. Results for an entire heating season are presented. Overall it is shown that shutters and insulation are the most important elements in the design of energy conserving structures for the north. Thermal mass plays a lesser role, especially during the mid-winter months when direct solar gain is balanced by the building envelope losses.
    • Passively encouraging offline networking in small, concentrated communities through UI/UX design

      Mitchell, Addeline; Metzgar, Jonathan; Lawlor, Orion; Chappell, Glenn (2019-05)
      The goal of this project is to identify whether it is possible to encourage users to communicate with one an other face-to-face through User Interface (UI) and User Experience (UX) design. It is well known that users can be maliciously manipulated by design elements and that concerns have been raised about the effects o f social media on interpersonal communication. The key is to find non-harmful means of guiding users to the desired action of speaking face-to-face with others. User testing for a custom web app was conducted for the purposes of this project. It is hoped that the results will provide developers with new consideration for UI and UX design.
    • Patterns and potential solutions to coastal geohazards at Golovin, Alaska

      Smith, Jacquelyn R.; Misra, Debasmita; Huang, Scott; Kinsman, Nicole (2014-05)
      The objective of this research is to measure the localized potential for shoreline change and flooding on the Golovin spit, Alaska. Long-term trends of shoreline change have been measured using multi-temporal aerial photography and satellite imagery from 1972-2013, while seasonal and annual changes in shoreline geometry have been measured by re-surveying the beach in July 2012, July 2013, and October 2013. The local bathymetry was updated with data derived from the WorldView-2 satellite to increase the spatial resolution of nearshore topography. These inputs were then integrated to establish an XBeach 1-dimensional numerical model connecting offshore storm water elevations to nearshore dynamics. The spit was found to experience episodic erosion of beach sediments, followed by sediment accretion. This resulted in a dynamic position of the shoreline, with no long-term trend in either the offshore or landward directions. Modeled storms resulted in inundation of low elevations of the spit at a 5- year return interval, with inundation of infrastructure on a 25-year return interval. The modeled results suggest overwash of the entire spit at the 50-100-year return interval. All models were based on the best available forcing data from hindcast modeling. Reinforcing and increasing the elevation of a temporary berm and/or a permanent levee structure, using a 25-year return interval as a design parameter, would help to reduce localized flooding on the spit, and may be considered in the future.
    • Performance analysis for remote power systems in rural Alaska

      Chubb, Tyler (2004-12)
      Due to the logistical difficulties involved in maintaining a rural Alaskan power generation facility, it is extremely important that the system function as efficiently as possible. Presently, many rural generation systems are not equipped with automated monitoring that enables knowledgeable personnel to view the performance of the system from a distant location. Consequently, system deficiencies resulting in increased fuel consumption and operating expense often go unnoticed as do potential system improvements. This thesis describes the design and implementation of a sophisticated monitoring system that consists of measurement sensors connected to an internet enabled data recorder. The monitoring system was used to continuously record the various forms of energy entering and leaving a diesel generator operating on the UAF campus. While in operation, the monitoring system was instrumental in identifying several measures that could be taken to improve the operating efficiency of the generator and also provided sufficient means to examine the economic feasibility of their implementation. The measures that were examined included heat recovery, conditioning of output power, and improvement of operating techniques.
    • Performance analysis of capture of heat energy from diesel engine exhaust

      Raghupatruni, Prasada Rao (2007-08)
      Diesel generators produce electrical power. New diesel generators, which use turbochargers, release a significant amount of heat energy from the turbocharger after coolers. Another significant amount of heat energy released from diesel engines and normally not captured for useful applications is the heat released from exhaust manifolds. This project discusses the design, installation, instrumentation, performance measurement and performance analysis of an exhaust heat recovery system for a new diesel generator, which has injection timing control. A diesel generator releases about one-third of its fuel energy in exhaust heat. The main aspect of this project is to study heat recovery from the exhaust of a diesel generator for heating purposes. The amount of heat liberated from the exhaust can be used both for the space and floor heating. This project covers the work for the selection of a desired heat recovery system as well as an analysis of the results of the selected heat recovery system. The amount of heat recovered from the exhaust by the heat recovery system was 50% of the total amount of heat present in the exhaust. No corrosion spots were found on the heat exchanger during the heat recovery system run time.
    • Performance Analysis of the Dowling Multi-lane Roundabouts in Anchorage, Alaska

      Lee, Ming (Alaska University Transportation Center, Alaska Department of Transportation and Public Facilities, 2010)
    • Performance analysis of three nanofluids in liquid to gas and liquid to liquid heat exchangers

      Ray, Dustin R.; Das, Debendra; Lin, Chuen-Sen; Kim, Sun Woo (2013-12)
      One purpose of this research was to analyze the thermal and fluid dynamic performance of nanofluids in an automotive radiator (liquid to gas). Detailed computations were performed on an automotive radiator using three different nanofluids containing aluminum oxide, copper oxide and silicon dioxide nanoparticles dispersed in the base fluid, 60:40 ethylene glycol and water (EG/W) by mass. The computational scheme adopted was the effectiveness-Number of Transfer Unit (� -- NTU) method encoded in Matlab. The computational scheme was validated by comparing the predicted results with that of the base fluid reported by other researchers. Then, the scheme was adapted to compute the performance of nanofluids. Results show that a dilute 1% volumetric concentration of nanoparticles can have substantial savings in the pumping power or surface area of the heat exchanger, while transferring the same amount of heat as the base fluid. The second purpose of this research was to carry out experimental and theoretical studies for a plate heat exchanger (PHE). A benchmark test was performed with the minichannel PHE to validate the test apparatus with water. Next, using a 0.5% aluminum oxide nanoparticle concentration dispersed in EG/W preliminary correlations for the Nusselt number and the friction factor for nanofluid flow in a PHE were derived. Then, a theoretical study was conducted to compare the performance of three nanofluids comprised of aluminum oxide, copper oxide and silicon dioxide nanoparticles in EG/W. This theoretical analysis was conducted using the � -- NTU method. The operational parameters were set by the active thermal control system currently under design by NASA. The analysis showed that for a dilute particle volumetric concentration of 1%, all the nanofluids showed improvements in their performance over the base fluid by reducing the pumping power and surface area of the PHE.
    • Performance considerations for horiznontal [sic] and unconventional wellbore configurations

      Deshpande, Mahesh (2002-08)
      The goal of this study was to investigate the performance of horizontal and unconventional well configurations and formulate guidelines for selecting optimum configuration. The simulation model was validated by comparing the productivity of numerical model for a horizontal well with the analytical models. The productivity of horizontal, snake wells and fishbone wellbore configurations was studied by varying four parameters, vertical position of well in the payzone, permeability anisotropy, partial completion and well length. Effect of friction loss correlations on estimation of well productivity losses was also studied. The study concludes that the ratio vertical position of well, Zw to the payzone thickness, h decreases the productivity of the wells increases. There is no significant change in performance of the wells for different configurations. As the permeability anisotropy ratio decreases the productivity decreases. The cumulative production does not decrease by half when the perforated well length is decreased by half. Also, the productivity index increases with increase in well length. Based on the results obtained we formulate guidelines for selecting well bore configurations. The results of this study can be applied to the design of horizontal and unconventional well configurations to aid reservoir management.
    • Performance of an air convection embankment over ice-rich permafrost: instrumentation, monitoring, and modeling

      Jensen, David D.; Darrow, Margaret M.; Shur, Yuri; Huang, Scott L. (2015-05)
      Construction and monitoring of roadway embankments over ice-rich permafrost present unique challenges. The air convection embankment (ACE) is a relatively new design developed to reduce thaw settlement over ice-rich permafrost. Monitoring ACE temperatures and deformation allows for evaluation of embankment performance to improve ACE designs, and numerical modeling of an ACE can be used to estimate long-term thermal stability. For this research, geotechnical instrumentation was installed in an ACE with thermal berm located near Chicken, Alaska. A digital temperature acquisition cable (TAC) and a MEMS-based in-place inclinometer were installed at the base of the embankment and evaluated for performance over a one-year period, and two-dimensional thermal modeling of the ACE and thermal berm was conducted. Temperature and deformation measurements from the site were analyzed to assess embankment performance, while modeled and measured embankment temperatures were compared to assess model validity. Results suggest that the TAC and in-place inclinometer demonstrate acceptable performance for monitoring embankment temperature and deformation, respectively, over ice-rich permafrost. The modeled embankment temperatures demonstrated a similar trend to measured temperatures, with temperatures beneath the thermal berm warmer than beneath the ACE; however, the mean modeled temperatures differed from those measured by -5°F for the thermal berm and -2°F and -9°F for a snow-covered and plowed ACE, respectively. Model results for a plowed ACE showed increased performance and a 7°F decrease in mean annual temperature compared to a snow covered ACE. Numerical modeling results and measured embankment temperatures and deformation suggest the ACE will remain stable while the thermal berm will experience thaw settlement until thermal equilibrium is reached. Foundation soil temperatures are expected to grow colder beneath the ACE and warmer beneath the thermal berm.
    • Performance of shallow anchor in ice-rich silt

      Lin, Chuang; 林闯; Zhang, Xiong; Shur, Yuri; Liu, Jenny; Connor, Billy (2014-12)
      Shallow anchor systems have been widely used for decades due to their time and cost efficiency. Yet when it comes to cold regions like Alaska, new challenges caused by the harsh environment need to be resolved before they are used extensively in cold regions. One challenge associated with anchor installation could be the potential thawing of warm permafrost due to the grout mortar hydration, which might undermine the capacity of the anchor. Another challenge is that due to low temperature the grout may cure slower or not cure at all, which will also result in a significant decrease in the ultimate strength of the anchor. Field tests were conducted to evaluate the performance of shallow anchors including duckbill anchors and grouted anchors with three types of different grouting materials, including Microsil Anchor Grout, Bentonite Clay and a newly-developed Antifreeze Grout Mortar. Constant-load creep test and pullout test were conducted to evaluate the performance of the anchors. Test results indicated that the anchors grouted with Antifreeze Grout Mortar caused the least permafrost disturbance and degradation, gained the largest tensile strength, exhibited the least creep displacement, and showed relatively large pullout capacity, and thus achieved the best performance among all types of shallow anchors.
    • Performance of Tencate Mirafi PGM-G4 Interlayer-Reinforced Asphalt Pavements in Alaska

      Li, Peng; Liu, Jenny; Eckman, Paul (Alaska University Transportation Center, 2014-08)
      Geosynthetics has been used in hot mix asphalt (HMA) overlays in a variety of design and construction situations for more than three decades. A number of positive benefits have been identified such as waterproofing control for base and subgrade protection, improved fatigue resistance and reduced propagation of reflective cracks. In cold regions such as Alaska and other northern states, pavements are more prone to distresses due to extreme climatic conditions. Research is needed to explore how interlayers functions in asphalt pavements in cold regions. The interlayers used for pavement reinforcement applications and available in the market are primarily biaxial. Biaxial grids with equal strength in both the machine and cross machine directions allow stress transfer at low strain mainly in longitudinal and transverse directions. The new PGM-G4 paving composite developed by Tencate Geosynthetics contains multi-axial fiberglass filament yarn, which changes the aperture geometry from a rectangular to a quad angular grid structure. This unique feature improves the structure radial stiffness and efficiently distributes stress from surface layer to the geogrid throughout the full 360o. This isotropic feature could deliver optimal asphalt concrete (AC)/grid interaction and more efficient reinforcement. There is a need to identify/validate its expected performance and added value over conventional biaxial grids. Hence, a study has been conducted on interlayer-reinforced asphalt pavements in Alaska that included two phases: laboratory index testing (Phase I) and field performance evaluation (Phase II). Phase I focused on laboratory evaluation of engineering properties of PGM-G4 composite paving grid-reinforced asphalt pavement structure and comparison with other types of interlayers. Five types of interlayers were evaluated in this study for various laboratory tests and they were PGM-G4 (multi-axial composite grid), PGM-G100/100 and PGM-G50/50 (bi-axial composite grid), TruPave® (engineered paving fiberglass and polyester hybrid mat), and MPV500 (conventional polypropylene interlayer). The performance tests included asphalt retention and grab strength tests of interlayers, and shear strength, permeability and indirect tension (IDT) tests of interlayer-reinforced asphalt mixtures. Further, a typical Alaska flexible pavement structure was used, and pavement structure analyses and simulation were conducted by Bisar, Alaska Flexible Pavement Design (AKFPD) and ABAQUS programs to investigate the effects of paving interlayers on the pavement performance.
    • 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.
    • Performance Prediction Of A Folding Fin Aircraft Rocket Using Datcom, Sens5D, And 6Dof Gem

      Kralewski, Sara Louise; Goering, Douglas; Lin, Chuen-Sen; Das, Debendra (1998)
      An approach for the performance prediction of a Folding Fin Aircraft Rocket (FFAR) is presented. This prediction was compiled by calculating the gravimetrics, aerodynamics, and trajectory for a FFAR. The trajectory analysis utilized four computer codes: Rogers Aeroscience Rocket Performance Software, NASA Wallops Sens5d Trajectory and Wind-Sensitivity Calculations for Unguided Rockets, the United States Air Force (USAF) Stability and Control DATCOM, and the NASA Langley Research Center LRC-MASS program (GEM). Computations were performed for a rigid body configuration. This analysis was compared to radar data collected during the flight of a FFAR launched in February 1997 at the Poker-Flat Research Range. The comparison shows good agreement between the flight data and the predicted apogee and impact point of the vehicle. In addition, static and dynamic stability analyses were completed for the FFAR. <p>
    • Permafrost Database Development, Characterization, and Mapping for Northern Alaska

      Jorgenson, M. Torre; Kanevskiy, Mikhail; Shur, Yuri; Grunblatt, Jess; Ping, Chien-Lu; Michaelson, Gary (2014-10-31)
    • Permafrost geosystem assessment at the Beaver Creek Road experimental site (Alaska Highway, Yukon, Canada)

      Stephani, Eva; Shur, Yuri; Fortier, Daniel; Kanevskiy, Mikhail; Connor, Billy (2013-05)
      An experimental site testing a range of engineering techniques for mitigating permafrost degradation along the Alaska Highway has been established in 2008 at Beaver Creek (Yukon, Canada). Based on the hypothesis that permafrost has a distinctive sensitivity to climate and terrain conditions at a local scale, a geosystem approach, which considers a set of components (e.g. permafrost, embankment, vegetation, hydrology and hydrogeology) and accounts for dynamics within a system, was applied to obtain a better understanding of local permafrost conditions and changes within the system. Therefore, this assessment, for ultimately measuring performance of the mitigation techniques, integrated the permafrost conditions, in terms of cryostratigraphic units and soil properties, with local climate, natural terrain and embankment conditions. The author, who participated in the site establishment, its baseline investigations and monitoring programs, presents here the baseline geosystem studies at the Beaver Creek Road Experimental Site with an emphasis on permafrost.