Comparative Performance of Different Warm Mix Asphalt Technologies under the Influence of High Aircraft Tire Pressure and Temperature

2021 ◽  
pp. 036119812110007
Author(s):  
Navneet Garg ◽  
Hasan Kazmee ◽  
Lia Ricalde
Keyword(s):  
Federal Aviation Administration ◽  
Warm Mix Asphalt ◽  
Test Cycle ◽  
Tire Pressure ◽  
Wheel Load ◽  
Comparative Performance ◽  
Chemical Additive ◽  
The North ◽  
Laboratory Characterization ◽  
Lower Temperature

Warm mix asphalt (WMA) technologies allow the production and placement of asphalt concrete materials at a lower temperature than the traditional hot mix asphalt (HMA). These materials simultaneously reduce the production fuel costs, increase the available hauling distance, lengthen the paving season, are eco-friendly, and ensure safer working conditions. Airport authorities can use such materials for construction applications to minimize the downtime and user-delay costs. However, the existing Federal Aviation Administration (FAA) construction specifications do not provide guidance on the implementation of such technologies, especially under the conditions created by aircraft with high tire pressure. To this end, the FAA National Airport Pavement and Materials Research Center (NAPMRC) conducted accelerated pavement tests as part of Test Cycle 1 (TC-1) to study the application potential of WMA (using chemical additive) on airport pavements. TC-1 results showed WMA performance was comparable to P-401 HMA performance in rutting. Test Cycle 2 (TC-2) study investigated the rutting performance of chemical, organic, and hybrid additive-based warm mixes alongside an FAA specification P-401 HMA counterpart. Four different test lanes were constructed accordingly in the outdoor area of NAPMRC, each encompassing three different test sections. Using the sixth-generation airport heavy vehicle simulator (HVS-A), sections on the north side of the test lanes were trafficked with 61.3 kips (272.7 kN) moving wheel load at a controlled temperature of 120°F (48.9°C). The chemical additive-based warm mix appeared to exhibit comparable performance to the HMA. A laboratory characterization effort also seemed to corroborate the rutting observations from traffic tests.

scholarly journals Analysis of the Actual Contact Surface of Selected Aircraft Tires with the Airport Pavement as a Function of Pressure and Vertical Load

Coatings ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 591
Author(s):  
Mariusz Wesołowski ◽  
Krzysztof Blacha ◽  
Paweł Pietruszewski ◽  
Paweł Iwanowski
Keyword(s):  
Contact Area ◽  
Contact Surface ◽  
Load Capacity ◽  
Surface Friction ◽  
Vertical Load ◽  
Tire Pressure ◽  
Wheel Load ◽  
Friction Tester ◽  
Flight Operations ◽  
Research Studies

The contact surface of the wheel with the airport surface is important for the safety of flight operations in the ground manoeuvring area. The area of the contact surface, its shape and stress distribution at the pavement surface are the subject of many scientists’ considerations. However, there are only a few research studies which include pressure and vertical load directly and its influence on tire-pavement contact area. There are no research studies which take into account aircraft tires. This work is a piece of an extensive research project which aims to develop a device and a method for continuous measurement of the natural airport pavement’s load capacity. One of the work elements was to estimate the relationship between wheel pressure and wheel pressure on the surface, and the area of the contact surface. The results of the research are presented in this article. Global experience in this field is cited at the beginning of the article. Then, the theoretical basis for calculating the wheel with the road surface contact area was presented. Next, the author’s research views and measurement method are presented. Finally, the obtained test results and comments are shown. The tests were carried out for four types of tires. Two of them were airplane tires from the PZL M28 Skytruck/Bryza and Sukhoi Su-22 aircraft. Two more came from the airport ASFT (airport surface friction tester) friction tester-one smooth ASTM; the other smooth retreaded type T520. The tires were tested in a pressure range from 200 to 800 kPa. The range of vertical wheel load on the pavement was 3.23–25.93 kN for airplane tires, and 0.8–4.0 kN for friction tester tires. The tests proved a significant influence of the wheel pressure value and wheel pressure on the surface on the obtained contact surface area of the wheel with the surface. In addition, it was noted that the final shape and size of the contact surface is affected by factors other than wheel pressure, tire pressure and dimensions.

An Optimization Model for Selecting Sample Days

2021 ◽  
pp. 2050052
Author(s):  
Tao Li
Keyword(s):  
North Atlantic ◽  
Optimization Model ◽  
Federal Aviation Administration ◽  
Selection Method ◽  
North Atlantic Region ◽  
Atlantic Region ◽  
Managerial Decisions ◽  
The North ◽  
The North Atlantic ◽  
The U.S

Sample day selection method plays an important role in managerial decisions which require analyses that are prohibitively expensive to apply to a large number of days. We develop a general sample day selection model that selects sample days based on the cumulative distributions of airspace conditions and characteristics (C&C) by considering factors such as sampling targets, degree of diversity and coverage of the selected days. We introduce indicators that capture the airspace C&C of the North Atlantic region (NAT) and apply the model to select sample days for the NAT. The results show that the model outperforms the methods used by the U.S. Federal Aviation Administration.

Experimental study of forest soil resistance to cone penetration

2016 ◽  
Vol 6 (3) ◽  
pp. 188-196
Author(s):  
Устинов ◽  
Vladimir Ustinov
Keyword(s):  
Forest Soil ◽  
Physical And Mechanical Properties ◽  
Rolling Resistance ◽  
Cone Penetration ◽  
Tire Pressure ◽  
Wheel Load ◽  
Theoretical Dependence ◽  
Slip Ratio ◽  
Methods Of Calculation ◽  
Drawbar Pull

This article informs us about testing the theoretical dependence to calculate cone index re-garding the soil deformation module. Common methods of calculation tractive performance of wheeled mover do not allow to analyze the influence of the geometric parameters of wheeled mover,inner tire pressure, slip ratio, wheel load, as well as the physical and mechanical properties of forest soil on rolling resistance, net thrust and drawbar pull coefficient in complex.

Study on the Dynamic Wheel Load of Multi-Axle Vehicle Based on Distribute Loading Weight

2010 ◽  
Vol 159 ◽  
pp. 35-40
Author(s):  
Zhong Hong Dong
Keyword(s):  
Dynamic Load ◽  
Influence Factors ◽  
Vehicle Speed ◽  
Tire Pressure ◽  
Wheel Load ◽  
The Road ◽  
Road Roughness ◽  
Tire Stiffness ◽  
On The Road

To study the dynamic wheel load on the road, a dynamic multi-axle vehicle mode has been developed, which is based on distribute loading weight and treats tire stiffness as the function of tire pressure and wheel load. Taking a tractor-semitrailer as representative, the influence factors and the influence law of the dynamic load were studied. It is found that the load coefficient increases with the increase of road roughness, vehicle speed and tire pressure, yet it decreases with the increase of axle load. Combining the influences of road roughness, vehicle speed, axle load and tire pressure, the dynamic load coefficient is 1.14 for the level A road, 1.19 for the level B road, 1.27 for the level C road, and 1.36 for the level D road.

scholarly journals Performance Evaluation of Warm- and Hot-Mix Asphalt Mixtures Based on Laboratory and Accelerated Pavement Tests

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Yongjoo Kim ◽  
Jaejun Lee ◽  
Cheolmin Baek ◽  
Sunglin Yang ◽  
Sooahn Kwon ◽  
...  
Keyword(s):  
Asphalt Mixture ◽  
Warm Mix Asphalt ◽  
Strength Test ◽  
Asphalt Mixtures ◽  
Limited Data ◽  
Tensile Strength Test ◽  
Paving Asphalt ◽  
Dynamic Modulus Test ◽  
Indirect Tensile ◽  
Lower Temperature

A number of warm-mix asphalt (WMA) technologies are used to reduce the temperature at which the asphalt mixtures are produced and compacted, apparently without compromising the performance of the pavement. The main objective of this study is to determine whether the use of an innovative wax-based LEADCAP WMA additive influences the performance of the asphalt mixture, which is produced and compacted at significantly low temperatures. The WMA pavement using LEADCAP additive (WMA-LEADCAP) along with a control HMA pavement was evaluated with respect to their performances of rutting resistance, crack resistance, and viscoelastic property based on the laboratory dynamic modulus test, indirect tensile strength test, and in-door accelerated pavement test (APT) results. With the limited data carried out, the LEADCAP additive is effective in producing and paving asphalt mixture at approximately 30°C lower temperature than a control HMA mixture, and the performances of WMA-LEADCAP pavement are comparable to a control HMA pavement.

scholarly journals 763 PB 307 ENVIRONMENTAL CONTROL ON FLOWERING AND GROWTH OF LYSIMACHIA CONGESTIFLORA

HortScience ◽  
1994 ◽  
Vol 29 (5) ◽  
pp. 542c-542
Author(s):  
Donglin Zhang ◽  
Allan M. Armitage ◽  
James M. Affolter ◽  
Michael A. Dirr
Keyword(s):  
Environmental Control ◽  
Day Treatment ◽  
Dry Weight ◽  
High Irradiance ◽  
Flower Initiation ◽  
Low Light ◽  
The North ◽  
Long Day ◽  
Total Plant ◽  
Lower Temperature

Lysimachia congestiflora Wils. (Primulaceae) is a new crop for American nurseries and may be used as an annual in the north and a half-hardy perennial in the south. The purpose of this study was to investigate the influence of photoperiod, temperature, and irradiance on its flowering and growth. Three experiments were conducted with photoperiod of 8, 12, 16 hrs day-1, temperature of 10, 18, 26C, and irradiance of 100, 200, 300 μmol m-2s-1, respectively. Plant.9 given long day photoperiod (16 hours) flowered 21 and 34 days earlier, respectively, than plants at 12 sad 8 hour photoperiods. Plants under long day treatment produced more flowers than those at 8 and 12 hours. Plant dry weight did not differ between treatments, but plants grown in the long day treatment produced fewer but larger leaves. Total plant growth increased as temperature increased, but lower temperature (10C) decreased flower initiation and prevented flower development, while high temperature (26C) reduced the longevity of the open flowers. Flowering was accelerated and dry weight increased as plants were subjected to high irradiance levels. The results suggest that Lysimachia congestiflora is a quantitative long day plant. It should be grown under a photoperiod of at least 12 hours at a temperature of approximately 20C. Low light areas should be avoided and supplemental lighting to provide the long days may improve the plant quality.

scholarly journals CLASSIFYING AND MAPPING OF VEGETATED AREA IN AL- BAHA REGION, SAUDI ARABIA USING REMOTE SENSING. II. THE RELATIONSHIP BETWEEN ELEVATION, LAND SURFACE DAY TEMPERATURE, AND VEGETATION DENSITY.

2020 ◽  
pp. 81-84
Author(s):  
Abdullah Saleh Al-Ghamdi
Keyword(s):  
Remote Sensing ◽  
Saudi Arabia ◽  
Land Surface ◽  
Eastern Desert ◽  
High Density ◽  
Vegetation Density ◽  
Central Belt ◽  
The North ◽  
North Eastern ◽  
Lower Temperature

Classifying and mapping of vegetated area in Al- Baha region, Saudi Arabia using remote sensing shows that the medium-high density vegetation is mostly found at the central part of Al-Baha region separating the highlands and the low lands. Results obtained show that only 862.5 km2 (7.7%) Al-Baha region is covered with medium-high density vegetation found mainly at the 6-15km width horizontal central belt (at districts of Al-Mandaq, Al-Baha and south Baljurashi) along high foggy mountainous plateau. Whereas, about 65% of Al-Baha region has very low-none density vegetation mainly occurred extensively at Tihama low plain towards the Red Sea and at the north-eastern desert plain. In addition, study reveals that the highlands of Al-Baha have the most numbers of trees represents the areas of the highest elevations in the region (range between 1940 and 2366 m above sea level. This indicates that there is relationship between this elevation range with medium to high vegetation density. Similarly, the low surface temperatures are mainly located at the central belt across Al-Baha region. When overlaid with medium-high vegetation density zone with the temperature map, it was visually observed that it almost fit with lower temperature zone of less than 15°C. This also indicates that there is relationship between lower temperature with medium-high vegetation density.

Numerical Simulation of Bus Windshield Based on Heat Transfer with Impinging Jets

2013 ◽  
Vol 774-776 ◽  
pp. 284-289 ◽  
Author(s):  
Hua Li ◽  
Ji Chun Zhang ◽  
Ping Hui Huang ◽  
Ke Yan Liu
Keyword(s):  
Heat Transfer ◽  
Numerical Simulation ◽  
Jet Impingement ◽  
Impinging Jets ◽  
High Humidity ◽  
Moist Air ◽  
The North ◽  
Impingement Heat Transfer ◽  
Vapor Fraction ◽  
Lower Temperature

The maximum vapor fraction in the air decreases with the temperature falling. For the air which has the high humidity, the redundant vapor will condense into fog or freeze into ice if the moist air attained a new saturation in a lower temperature. The buses running in the north cold areas usually face this problem in winter. According to the theory of jet impingement heat transfer, this thesis analyzed the influences of angle between the windshield and impinging jets and also the distance between vents and dashboard edge on defrosting by a simplified bus model. It also put forward some suggestions about defrosting on buses.

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