Research Projects

Heated Airport Pavements

Project Duration

08-14-2013 to 07-20-2017

Project Summary

Maintaining operational safety and status of airport runways during snowfall events is a challenging issue that many airports are grappling with. According to FAA Advisory Circular 150/5370-17 (dated 2011), most transport category aircraft are prohibited from operating on runways covered by untreated ice or by more than 1/2 inch of snow or slush, although the limits vary with aircraft types. The surface traction of pavement is dramatically influenced by frozen precipitation in the form of ice, snow, or slush. This can seriously hamper smooth air traffic management operations and cause traffic delays at other airports. Ice and snow on transportation infrastructure systems add significant costs to the American economy via snow removal, damaged pavement and bridge surfaces and lost man-hours due to travel delay. It is imperative that both small and large airports maintain operational status during snowfall events to support the existing operations as well as the FAA's NextGen concept as mentioned in the Airport Technology Research Plan for the NextGen Decade (dated January 2012). 

Traditional deicing methods involving sand/chemical mixtures pose not only environmental concerns, but also can potentially result in creating Foreign Object Damage (FOD) to aircraft engines. Additionally, the costs of owning and operating snowplows can be substantial for many general aviation airports. Innovative concepts such as heated pavement systems, which can use either electric or renewable energy as a heat source, show good potential by providing enough heat to keep the surface temperature of the runway above freezing so that any frozen precipitation melts upon contact. The FAA has expressed an interest in investigating the concept of heating pavements at airports to assist with snow and ice removal. Recognizing the limitations of current practice and research on heated pavement technology, prudent use of heat on select areas of airfield pavements should be considered. Heated pavement areas to be considered should be limited to those areas where: (1) Benefits justify cost of installation and operation; (2) Mechanical methods of snow removal are difficult to accomplish or are not cost effective; (3) Operational safety is a factor; (4) Delays at critical locations within the airport cannot be tolerated; and (5) Use of chemical deicers is restricted/limited. The FAA has suggested that attention should be focused initially on the parking ramps. Potential benefits include greater safety for crews and passengers, both on the ground and in aircraft, improvement in airport capacity and throughput during winter operations, reduction in environmental impacts of chemical deicers, and more efficient turnaround of aircraft because conventional plowing is difficult under and around a parked aircraft. 

Over the past decade, a number of national and international research studies have investigated the use of alternative energy for anti-icing, deicing, and snow removal from bridge decks and highway pavements. Reportedly some efforts have been investigated using geothermal hydraulic and battery based electrical systems with limited success. The FAA has expressed concern that if any system is to be adopted it must be cost effective, both in terms of installation and operating costs. 

In this project we propose a 3-pronged approach to investigate the efficacy and cost effectiveness of new heated pavement technologies. We propose to investigate: the relative energy and monetary needs to remove snow from a slab by conducting an energy and financial viability analyses under Task 1-A; a hybrid approach combining electrically conductive concrete with lotus-leaf-inspired super-hydrophobic surfaces under Task 1-B; and the application of nano-coatings of low temperature phase change materials with the intent of preventing ice and slush formation under Task 1-C. We anticipate that these three tasks will run in parallel. Below, we briefly describe each task in detail.

 

TASK 1-A: Energy and Financial Viability

Project Description

Heated pavement systems have gained attention as desirable alternatives to current ice and snow removal practices, and make practical and economic sense for airport pavements frequently impacted by snow/ice during winter months. Recognizing the current limitations of heated pavement technology, prudent use of heat on select areas of airfield pavements should be considered. Heated pavement systems offer an alternative strategy for effectively mitigating the effects of winter contaminant by melting snow and preventing bonding to the pavement surface. Before successfully implementing a heated pavement technology on selected airfield pavement areas, research is needed to investigate energy saving benefits, as well as the economic and safety advantages.

 

Research Objectives

The first objective of this research is to assess the amount of energy required to heat a slab to above freezing temperature during a winter precipitation event, and compare it with the energy consumed using conventional approaches. Conventional approaches include plowing, use of chemicals (such as potassium acetate) and hauling off site. This evaluation will be useful in helping to assess the viability of other systems to be considered in this proposal. The second objective of the work is to investigate the economic advantages of a heated pavement, this will include factors such as operational savings and improved safety along with staffing needed to operate snow removal equipment. It is likely that these benefits will be significantly greater in high traffic airports than small GA airports and these will be assessed. The final aspect will be to appraise the initial installation costs of a heating system and ascertain how they may be absorbed over a period of time under operation.

 

TASK 1-B: Hybrid Heated Airport Pavements

 

Project Description

Maintaining operational safety and status of airport runways during snowfall events is a challenging issue that many airports are grappling with. The surface traction of pavement is dramatically influenced by frozen precipitation in the form of ice, snow, or slush. Traditional deicing methods involving sand/chemical mixtures pose not only environmental concerns, but also can potentially result in creating Foreign Object Damage (FOD) to aircraft engines. Recent research studies have highlighted the potential of using “electrically conductive concrete” (concrete mix containing a certain amount of electrically conductive materials in a regular concrete matrix, designed to enable electrical conduction) to prevent formation of ice on paved surfaces when connected to a power source. Also, recent progress made toward understanding the use of lotus-leaf-inspired superhydrophobic surfaces for the prevention of ice formation can have potential positive implications for airport pavement deicing. In this research, we will investigate the feasibility of developing and implementing a hybrid heated pavement system that will integrate the complimentary aspects of electrically conductive concrete and nano-engineered superhydrophic surfaces to keep the runway surface temperature above freezing during winter weather operations.

 

Research Objectives

The objective of this research is to develop a hybrid heated airport pavement system that can keep the runway surface temperature above freezing during winter weather operations.

 

TASK 1-C: Investigating the potential to use Phase Change Materials (PCM) to store heat in concrete pavement thereby reducing the need for anti-icing

 

Project Description

The prevalent methods for removal of snow and ice from aviation infrastructure are costly, have environmental impact, and can be labor intensive.  This work examines the potential to alter the properties of the pavement using phase change materials (PCM) (with or without heating technologies) as a way to reduce or eliminate the use of deicing and plowing.  PCM are frequently used to store thermal energy and have the potential to be used to revolutionize anti-icing practices in airfield pavements.  PCM’s can store energy from ambient, applied or solar sources. This project will examine the role that PCM may have in storing heat in pavements in an effort to delay and reduce the decrease in surface temperature. 

Research Objectives

  1. Review the literature regarding PCM in pavement and other applications
  2. Develop a model that identifies the ideal properties of the PCM
  3. Review potential PCM based on their effectiveness and cost
  4. Investigate the most effective methods to place PCM in concrete
  5. Evaluate the performance of the PCM in concrete 


The project will build and test full-scale samples to determine the conditions where PCM is sufficient to facilitate their use in snow and ice removal or the conditions where this can complement an alternative pavement heating system.  It is the intention that this project will provide necessary information that will place the FAA in a position at the end of this project to consider a full scale onsite trial implementation of PCM with information on ideal PCMs to use, how the PCM are most effectively placed in concrete, anticipated costs, and projected performance.

 

Expected Benefits of the Heated Airport Pavements Project

The overall impacts of this research will make winter air travel faster, more affordable, more accessible, more sustainable and safer for all parties involved.

FAA Technical Point of Contact

Benjamin Mahaffay - Federal Aviation Administration (benjamin.mahaffay@faa.gov)

Technical Point of Contact

Halil Ceylan - Iowa State University (hceylan@iastate.edu)

Researchers

Organizations

Lead Organization: Iowa State University

Other Participating Organizations