Design, construction, and performance of heated concrete pavements system

Ice and snow accumulation on airport paved surfaces has the potential to cause fatal accidents and monetary loss due to associated flight delays and cancellations. Traditional de-icing methods involving the application of chemicals or salt, and deployment of large machines can create negative environmental and structural impact on airport infrastructure systems. Such methods are also considered to be both labor-intensive and safety hazards, especially in congested areas such as aprons. In recent years, hydronic and/or electrically conductive concrete (ECON) heated pavement systems (HPS) have been receiving attention for mitigating problems associated with the presence of ice/snow on roadways and paved areas of airfields. In this study, the system requirements of electrically-conductive concrete (ECON) heated pavement systems were identified for their potential with respect to achieving cost-effective performance. A prototype small-scale ECON heated concrete slab was designed, constructed, and tested using an optimized ECON mixture recently developed at Iowa State University (ISU), to obtain the efficiency and performance results. This prototype ECON slab provided the lowest energy consumption and lowest energy cost among the electrically-heated pavement systems developed so far. The two-layer approach utilized in design and construction of the prototype ECON slab is cost-effective in terms of construction cost, energy consumption, and operational cost savings. Given the promising results from the ECON slab research studies, both the airport owner and the FAA have demonstrated interest in providing assistance and support in taking this technology developed in-house and implementing it full-scale on-site at the DSM airport, representing the first full-scale ECON-based HPS conducted and tested at a U.S. airport. Two ECON slabs were designed and constructed in 2016 at the General Aviation (GA) apron at the Des Moines International Airport (DSM), Iowa. Systematic design components were identified and construction procedures were developed and implemented for ECON-based HPS. Using sensor data collection, the performance of the remotely-operated ECON slabs was evaluated under real weather conditions at DSM during the 2016-2017 winter season, with results demonstrating that ECON-based HPS offer promising deicing and anti-icing capacities for providing uniform heat distribution and preventing snow and ice accumulation on the entire area of application under various winter weather conditions. Going forward, there is an imperative need to investigate and/or develop new technologies to best automate and accelerate the construction of large-scale heated pavements at airports. This study attempted to partially fulfill that need by conducting a detailed review of advanced pavement construction techniques and practices and evaluating their efficacy and applicability to construction of HPS at airports. System requirements of ECON and hydronic HPS were identified and laboratory experimental investigations were carried out to study their efficiency and performance results, leading to the development of a design procedure for large-scale HPS at airports. Advanced construction techniques and workflows for precast concrete (PC), two-lift paving, and concrete overlays for heated pavements were demonstrated using 3D visualizations to provide design and construction guidance for large-scale heated airport pavements. A 3-D finite element (FE) model was developed for ECON which can be used as a cost-effective evaluation tool for examining the effects of various design parameters on the time-dependent heating performance of ECON HPS design optimization

Construction Techniques for Electrically Conductive Heated Pavement Systems

Ice and snow accumulation on airport paved surfaces has the potential to cause fatal accidents and monetary loss due to flight delays and cancellations. Traditional de-icing methods involving the application of chemicals or salt and employing large machines can create negative environmental and structural impact on airport infrastructure systems. These methods are also considered to be labor intensive and a safety hazard, especially in congested areas such as aprons. Heated pavement systems using electrically conductive concrete (ECON) have been proposed as a promising alternative technology for preventing ice accumulation and mitigating the adverse effects of using traditional snow removal methods. The objective of this study is to present information and experience about the design, construction procedures, and performance of heated pavement systems using jointed plain concrete pavements for the construction of large-scale heated airport pavements. It is based on detailed field demonstration of the electrically conductive concrete (ECON) heated pavement system (HPS) at the north general aviation (GA) apron of the Des Moines International Airport (DSM) in Iowa, in collaboration with contractors, and airport staff representatives. The expected outcome of this study will help the construction industry to better understand optimal ECON construction methods

Carbon fiber-based electrically conductive concrete for salt-free deicing of pavements

Traditional methods of removing snow/ice from pavements involve application of deicing salts and mechanical removal that carry environmental concerns. In this study, the feasibility of applying carbon fiber-based electrically conductive concrete (ECON) in heated pavement systems (HPS) as an alternative to traditional methods was investigated. Optimum carbon fiber dosage to achieve desirable electrical conductivity and avoid excessive fiber use was determined by studying carbon fiber percolation in different cementitious composites. System design was evaluated by finite element (FE) analysis. Heating performance in terms of energy consumption regime was studied by quasi-long-term (460-day) experimental study using a prototype ECON slab. Percolation transition zone of carbon fiber in paste, mortar, and concrete were respectively 0.25–1% (Vol.), 0.6–1% (Vol.), and 0.5–0.75% (Vol.). Optimum fiber dosage in ECON with respect to conductivity was 0.75%, resulting in volume conductivity of 1.86 × 10−2 (S/cm) at 28 days and 1.22 × 10−2(S/cm) at 460 days of age. Electrical-energy-to-heat-energy conversion efficiency decreased from 66% at 28 days to 50% at 460-day age. The results showed that the studied technology could be effectively applied for ice/snow melting on pavement surfaces and provide a feasible alternative to traditional methods if the ECON mixing proportions and system configurations are made with necessary precautions

Advanced Construction Techniques for Heated Pavement Systems

12-C-GA-ISUIce and snow accumulations on paved surfaces in airports have the potential to cause flight delays and/or cancellations, pavement deterioration, and safety concerns. In recent years, hydronic and/or electrically conductive concrete (ECON) heated pavement systems (HPS) are receiving attention for mitigating problems associated with the presence of ice/snow on roadways and paved areas of airfields. The need to investigate and/or develop new technologies to best automate and accelerate the construction of large-scale heated pavements at airports is imperative. In this study, a detailed review of advanced pavement construction techniques and practices was conducted to evaluate their efficacy and applicability to construction of HPS at airports. System requirements of ECON and hydronic HPS were identified, and laboratory experimental investigations were performed to study their efficiency and performance results, leading to the development of a design procedure for large-scale HPS at airports. Advanced construction techniques and workflows, viz., precast concrete pavement, two-lift paving, and concrete overlays, for heated pavements were demonstrated through three-dimensional (3D) visualizations to provide design and construction guidance for large-scale heated pavement at airports. A 3D finite element model was developed for ECON that can be used as a cost-effective evaluation tool for examining the effects of various design parameters on the time-dependent heating performance of ECON HPS design optimization

Design, construction, and performance of heated concrete pavements system

Ice and snow accumulation on airport paved surfaces has the potential to cause fatal accidents and monetary loss due to associated flight delays and cancellations. Traditional de-icing methods involving the application of chemicals or salt, and deployment of large machines can create negative environmental and structural impact on airport infrastructure systems. Such methods are also considered to be both labor-intensive and safety hazards, especially in congested areas such as aprons. In recent years, hydronic and/or electrically conductive concrete (ECON) heated pavement systems (HPS) have been receiving attention for mitigating problems associated with the presence of ice/snow on roadways and paved areas of airfields. In this study, the system requirements of electrically-conductive concrete (ECON) heated pavement systems were identified for their potential with respect to achieving cost-effective performance. A prototype small-scale ECON heated concrete slab was designed, constructed, and tested using an optimized ECON mixture recently developed at Iowa State University (ISU), to obtain the efficiency and performance results. This prototype ECON slab provided the lowest energy consumption and lowest energy cost among the electrically-heated pavement systems developed so far. The two-layer approach utilized in design and construction of the prototype ECON slab is cost-effective in terms of construction cost, energy consumption, and operational cost savings. Given the promising results from the ECON slab research studies, both the airport owner and the FAA have demonstrated interest in providing assistance and support in taking this technology developed in-house and implementing it full-scale on-site at the DSM airport, representing the first full-scale ECON-based HPS conducted and tested at a U.S. airport. Two ECON slabs were designed and constructed in 2016 at the General Aviation (GA) apron at the Des Moines International Airport (DSM), Iowa. Systematic design components were identified and construction procedures were developed and implemented for ECON-based HPS. Using sensor data collection, the performance of the remotely-operated ECON slabs was evaluated under real weather conditions at DSM during the 2016-2017 winter season, with results demonstrating that ECON-based HPS offer promising deicing and anti-icing capacities for providing uniform heat distribution and preventing snow and ice accumulation on the entire area of application under various winter weather conditions. Going forward, there is an imperative need to investigate and/or develop new technologies to best automate and accelerate the construction of large-scale heated pavements at airports. This study attempted to partially fulfill that need by conducting a detailed review of advanced pavement construction techniques and practices and evaluating their efficacy and applicability to construction of HPS at airports. System requirements of ECON and hydronic HPS were identified and laboratory experimental investigations were carried out to study their efficiency and performance results, leading to the development of a design procedure for large-scale HPS at airports. Advanced construction techniques and workflows for precast concrete (PC), two-lift paving, and concrete overlays for heated pavements were demonstrated using 3D visualizations to provide design and construction guidance for large-scale heated airport pavements. A 3-D finite element (FE) model was developed for ECON which can be used as a cost-effective evaluation tool for examining the effects of various design parameters on the time-dependent heating performance of ECON HPS design optimization.</p

Electrically Conductive Mortar Characterization for Self-Heating Airfield Concrete Pavement Mix Design

The overall objective of this paper is to investigate the types and proportions of nano-carbon based conductive materials (carbon powders and fiber), the mixing procedures, and the characteristics of conductive mortar, including the heating performance, with a focus on optimizing self-heating ECON mix design with desirable electrical and mechanical properties for airfield pavement deicing applications. A state-of-the-art review on relevant literature was conducted to identify the various conductive materials that have been investigated in the past, their optimal concentration levels to achieve desirable system-level engineering properties, and the various challenges in optimizing the ECON mix design and achieving a cost-effective ECON system. In the experimental investigation, mortar specimens modified with conductive materials at different concentration levels were compared with untreated (control) specimens interms of electrical and mechanical properties. Conductivity and strength performance assessment of the experimental results revealed that 6-mm chopped carbon fiber (CCF) utilized in this study is capable of providing improved electrical conductivity in compar ison to carbon based conductive powders without loss of strength and workability. Among carbon based conductive powders, the coarsest graphite powder provides acceptable electrical conductivity improvement and lesser loss of strength and workability. Heating characteristic of conductive mortar indicates that conductive materials which can enhance ECON conductivity could provide heating performance improvement for airfield pavement deicing application

Electrically Conductive Mortar Characterization for Self-Heating Airfield Concrete Pavement Mix Design

The overall objective of this paper is to investigate the types and proportions of nano-carbon based conductive materials (carbon powders and fiber), the mixing procedures, and the characteristics of conductive mortar, including the heating performance, with a focus on optimizing self-heating ECON mix design with desirable electrical and mechanical properties for airfield pavement deicing applications. A state-of-the-art review on relevant literature was conducted to identify the various conductive materials that have been investigated in the past, their optimal concentration levels to achieve desirable system-level engineering properties, and the various challenges in optimizing the ECON mix design and achieving a cost-effective ECON system. In the experimental investigation, mortar specimens modified with conductive materials at different concentration levels were compared with untreated (control) specimens interms of electrical and mechanical properties. Conductivity and strength performance assessment of the experimental results revealed that 6-mm chopped carbon fiber (CCF) utilized in this study is capable of providing improved electrical conductivity in compar ison to carbon based conductive powders without loss of strength and workability. Among carbon based conductive powders, the coarsest graphite powder provides acceptable electrical conductivity improvement and lesser loss of strength and workability. Heating characteristic of conductive mortar indicates that conductive materials which can enhance ECON conductivity could provide heating performance improvement for airfield pavement deicing application.This article is published as Gopalakrishnan, Kasthurirangan, Halil Ceylan, Sunghwan Kim, Shuo Yang, and Hesham Abdualla. "Electrically conductive mortar characterization for self-heating airfield concrete pavement mix design." International Journal of Pavement Research and Technology 8, no. 5 (2015): 315-324. doi: 10.6135/ijprt.org.tw/2015.8(5).315. Posted with permission.</p

Hydronic Heated Pavement System Using Precast Concrete Pavement for Airport Applications

The use of deicing chemical has the potential to cause environmental and safety concerns and pavement deterioration. Hydronic heated pavement systems (HHPS) have been widely used to melt or prevent ice and snow accumulation on paved surfaces. HHPS uses heated fluid circulated through pipes embedded in the concrete pavement to warm the surface of the concrete. The objective of this study is to develop a conceptual design framework and construction guidance for large-scale HHPS using precast concrete pavement (PCP) technology to expedite construction work and minimize air travel disruption. The detailed design and 3-D visualization of construction procedures has been developed for HHPS using PCP technology. The outcome of this study will help contractors and transportation agencies to envision the constructability of different components in HHPS, including tubing patterns and construction procedures.This is a manuscript of a proceeding published as Abdualla, Hesham, Halil Ceylan, Sunghwan Kim, Peter C. Taylor, Kasthurirangan Gopalakrishnan, and Kristen Cetin. "Hydronic Heated Pavement System Using Precast Concrete Pavement for Airport Applications." In International Conference on Transportation and Development (2018): 16. doi: 10.1061/9780784481554.003. Posted with permission.</p

Construction Techniques for Electrically Conductive Heated Pavement Systems

Ice and snow accumulation on airport paved surfaces has the potential to cause fatal accidents and monetary loss due to flight delays and cancellations. Traditional de-icing methods involving the application of chemicals or salt and employing large machines can create negative environmental and structural impact on airport infrastructure systems. These methods are also considered to be labor intensive and a safety hazard, especially in congested areas such as aprons. Heated pavement systems using electrically conductive concrete (ECON) have been proposed as a promising alternative technology for preventing ice accumulation and mitigating the adverse effects of using traditional snow removal methods. The objective of this study is to present information and experience about the design, construction procedures, and performance of heated pavement systems using jointed plain concrete pavements for the construction of large-scale heated airport pavements. It is based on detailed field demonstration of the electrically conductive concrete (ECON) heated pavement system (HPS) at the north general aviation (GA) apron of the Des Moines International Airport (DSM) in Iowa, in collaboration with contractors, and airport staff representatives. The expected outcome of this study will help the construction industry to better understand optimal ECON construction methods.This is a manuscript of a proceeding published as Abdualla, Hesham, Halil Ceylan, Kristen S. Cetin, Sunghwan Kim, Peter C. Taylor, Mani Mina, Bora Cetin, Kasthurirangan Gopalakrishnan, and Sajed Sadati. "Construction Techniques for Electrically Conductive Heated Pavement Systems." In Construction Research Congress 2018, pp. 551-561. DOI: 10.1061/9780784481295.055. Posted with permission.</p

Carbon fiber-based electrically conductive concrete for salt-free deicing of pavements

Traditional methods of removing snow/ice from pavements involve application of deicing salts and mechanical removal that carry environmental concerns. In this study, the feasibility of applying carbon fiber-based electrically conductive concrete (ECON) in heated pavement systems (HPS) as an alternative to traditional methods was investigated. Optimum carbon fiber dosage to achieve desirable electrical conductivity and avoid excessive fiber use was determined by studying carbon fiber percolation in different cementitious composites. System design was evaluated by finite element (FE) analysis. Heating performance in terms of energy consumption regime was studied by quasi-long-term (460-day) experimental study using a prototype ECON slab. Percolation transition zone of carbon fiber in paste, mortar, and concrete were respectively 0.25–1% (Vol.), 0.6–1% (Vol.), and 0.5–0.75% (Vol.). Optimum fiber dosage in ECON with respect to conductivity was 0.75%, resulting in volume conductivity of 1.86 × 10−2 (S/cm) at 28 days and 1.22 × 10−2(S/cm) at 460 days of age. Electrical-energy-to-heat-energy conversion efficiency decreased from 66% at 28 days to 50% at 460-day age. The results showed that the studied technology could be effectively applied for ice/snow melting on pavement surfaces and provide a feasible alternative to traditional methods if the ECON mixing proportions and system configurations are made with necessary precautions.This is a manuscript of an article published as Sassani, Alireza, Ali Arabzadeh, Halil Ceylan, Sunghwan Kim, SM Sajed Sadati, Kasthurirangan Gopalakrishnan, Peter C. Taylor, and Hesham Abdualla. "Carbon fiber-based electrically conductive concrete for salt-free deicing of pavements." Journal of Cleaner Production 203 (2018): 799-809. DOI: 10.1016/j.jclepro.2018.08.315. Posted with permission.</p