Airport Pavement Research Articles

Study of expansive soil stabilized with agricultural waste

During any construction on soil surface such as construction of road and airport pavements, compaction of the soil is required and soil stabilization plays a vital role. Various characteristics of soil should be optimized with different factors. Expansive soil has property of swelling when moisture content increases and shrinking when water gets evaporated. Rice husk is a major agricultural waste that is easily available in in India and is generally burnt to get rice husk ash (RHA). This study has been aimed to get dual benefit, first to stabilize expansive soil by addition of RHA and second to effectively utilize RHA, the agricultural waste. It has been observed that at 12% RHA in presence of 5% cement can be effectively used to improve plasticity of soil and CBR value resulting in effective soil stabilization. Thus, the research demonstrates that agricultural waste has efficient use in soil stabilization.

Stabilization of the subsoil and leveling of concrete paving slabs

Abstract: In the process of using airport pavements, destructive processes of concrete slabs caused by operational loads and environmental factors are observed. One of the most common damages to concrete surfaces is thresholds (faults) - vertical displacements of the edges of the slabs or displacements on the cracks of the slabs, resulting from damage to the subsoil or foundation. Performing periodic inspections of the technical condition of the pavement allows you to monitor the changes taking place and at the same time plan repairs, which is associated with the selection of appropriate materials for their implementation. This article is devoted to the issue of stabilization and leveling of concrete pavement slabs in the low-pressure injection technology with the use of specialized injection materials (resins). The technology of board re-leveling is used in places of settlement, permanently strengthening the subsoil or substructure, as well as allowing to restore the required parameters of surface evenness. The article presents the results of laboratory tests as well as the results of field tests carried out before and after the injection works, based on the example of works carried out at one of the airport facilities in Poland. The article presents, among others the results of the load-bearing and evenness tests of the pavement and the results of the tests with the use of GPR. The presented technology belongs to non-invasive repair solutions and short-term works. Keywords: concrete pavement; Geotechnical injections; Keystroke plates

Fast material disintegration of cement concrete in the exterior

Over the recent years the amount of fast destruction defects of cement paste matrix has increased markedly for exposed concrete structures of highway and airport pavements. The accelerated destruction of silicate structure is unusual due to its irregular occurrence. It only occurs at 30 to 50% of newly built pavements (in continuous segments). The issue is applicable to loaded as well as unloaded pavements. Detailed diagnostics found that the probable cause is based on concurrently occurring expansive reactions in capillaries, cracks and pores in the cement paste matrix. In defect spots the presence of several expansive substances was proven, wherein the biggest question poses the unexpectedly high potassium concentration. Potassium is only contained at best in trace amounts in road concrete input components in the Czech Republic. Neither existing regulations nor standards sufficiently deal with this type of defects of cement concretes. If they mention the existence of this issue at all, they are just limited to recommendations. Since the modification of the existing commercially produced cements to pavements is still improbable, the solutions to this issue seem problematic.

Texture of airport pavements in terms of their drainage efficiency

Abstract: Characteristics of the drainage of the surface movement area of airports, and more precisely the rapid drainage of water from the surface, is the main safety factor taken into account at the stage of designing, building, and maintaining the movement area and adjacent areas. Drainage of water from the pavement is a basic requirement and serves to reduce the thickness of the water layer on the surface. Adequate drainage is ensured primarily by surfaces with a suitable slope, both longitudinally and transversely (natural water drainage). On the other hand, dynamic drainage is achieved through the texture of the pavement. The paper presents the results of research on the texture of airport pavements and their analysis in relation to the current requirements. In the tests, apart from the currently used point measurement method, an innovative method of assessing anti-skid properties was used, which allowed for the simultaneous measurement of the friction coefficient µ and a new coefficient of continuous mean profile depth and CMPTD texture. The obtained results allowed us to present conclusions that when assessing the texture of airport pavements and thus designing structural solutions in terms of their drainage, it is reasonable to take into account the technology of its implementation (cement concrete or asphalt concrete). Keywords: Drainage of airport pavements; Texture of airport pavements; Safety of air operations

Artificial Neural Network Prediction of Airport Pavement Moduli Using Interpolated Surface Deflection Data

Establishing the structural integrity of an airport pavement is crucial to assess its remaining life and implement strategies or priorities for action. In this context, the elastic modulus represents an effective indicator of the condition of the pavement which can be calculated through back-calculation procedures starting from surface deflections, obtained from a non-destructive test (such as the Heavy Weight Deflectometer). Nevertheless, the conventional inverse engineering analysis involves the use of an axial-symmetric pavement finite-element program able to evaluate stiffness values exclusively at the deflection measuring points. This study presents an alternative methodology for spatial modelling of the load- bearing capacity of the runway surface pavement layer from deflection data measured at specific points, using Shallow Artificial Neural Networks. The search of the optimal neural model hyperparameters has been addressed through a Bayesian Optimization procedure and a 5-fold cross-validation has been implemented for a fair performance evaluation, given the limited number of deflection measures available. Once the optimal model has been defined, the measured surface deflection data were linearly interpolated and resampled gridding data were used as a new input matrix of the neural model to predict the expected value of elastic moduli at non-sampled points on the runway. The optimal BO model has returned very satisfactory results with a value of Pearson Coefficient R averaged over 5-fold equal to 0.96597 and of Mean Squared Error averaged over 5-fold equal to 0.01849. In such a way, a contour map of the runway stiffness has been drawn, to provide a support tool for the planning of intervention priorities.

Technical diagnostics and reliability development of concrete airfield pavements in modernization and reconstruction progress

Abstract: The technical reliability of concrete airport pavements evolves mainly when the project and its technical and functional solutions in all types of industry works is being developed. In the operation process, the technical reliability of the pavement can be shaped as a result of its' modernization and reconstruction. The effect depends primarily on the quality of the works. Currently, the contractors have high-quality materials and specialized equipment minimising human factor in the process of preparing and placing the concrete mix. Potentially high qualifications of technical personnel and other members of the works crew should be a guarantee of high quality works. The operation process must be characterized by a high level of technical culture and rational maintenance procedures. The publication presents the theoretical model of modernized and reconstructed airport's reliability, paying particular attention to the accuracy and efficiency of its technological implementation. Keywords: Pavement reliability; Quality of pavement works; Operational condition; AFE (airport functional elements)

Airport grating as a fast and effective method of improving the load-bearing capacity of natural airport pavements

Abstract: Natural airport surfaces, which are functional elements of airports, such as: runway shoulders, frontal lanes, emergency runway, or working runway, play an important role in the safety of air operations. Both the International Civil Aviation Organization (ICAO) and the European Union Aviation Safety Agency (EASA) define the load-bearing capacity requirements that natural airport pavements should meet. These documents specify the required California Bearing Ratio (CBR) of 15-20% at a depth of 15 cm below ground level. The previous field tests in civil and military airports have shown that the load-bearing capacity of natural airport pavements sometimes does not meet certain requirements. Due to the fact that airports cannot afford to shut down the airport for a long time, it is reasonable to search for innovative methods of improving the load-bearing capacity of natural airport pavements, which will be effective and quick to implement. Such a method may be the use of an airport grating pressed directly into the natural airport pavement. Keywords: Load capacity; CBR; Natural airport pavement; Safety of air operations

Atmospheric corrosivity assessment on the basis of standard specimens’ corrosion rates within the military air bases

Abstract: Atmospheric corrosion is one of the parameters characterizing the technical condition of the functional elements of airport pavements - it allows to determine the degree of pavement degradation, estimate the appropriate frequency of periodic inspections and take appropriate measures to keep airfield pavements in permanent technical availability. In order to determine the corrosion resistance of the cement and asphalt concrete airfield pavement, atmospheric corrosivity tests determined on the basis of standard specimens exposure and determination of corrosion rates, form and appearance of deteriorations, as well as changes in physical properties at regular intervals are carried out. The samples were exposed to atmospheric conditions at military airport facilities. The article presents the rcorr corrosion rate results of low-carbon steel, zinc, copper and aluminum standard specimens obtained from selected airports of the Polish Armed Forces, starting from 2015. Then, the corrosivity categories of the atmosphere were determined on the basis of the performed measurements. Keywords: Atmospheric corrosion; Corrosion rate; Standard specimens; Military air bases

Settlement Analysis of Dredged Material and Its Stabilization Using Surkhi/Brick Dust

Abstract: Soil stabilization is the phenomenon by virtue of which the soils are altered to enhance their physical Properties. The process aims to increase the shear Strength of soil thus improving its load bearing capacity to support pavements and foundations. Diverse range of soil materials varying from Expansive clays to granular materials can be treated by a diverse set of Additives like silica, lime, fly-ash, cement and so on. In J&K, the most common types of soils are the alluvial soils which get deposited in river beds as a result of sedimentation. River Jhelum in J&K is one of the major hotspots for accumulated sediments with an estimate of about 36 lakh cubic meters of sediments in its river bed, leaving very little space in it to take excess water. Subsequently, it is severely threatened by the Phenomena of still higher levels of sedimentation and hence consequent Floods. Dredging practices are a challenge for the maintenance of rivers and their Spillways. In Geotechnical Engineering, the valorisation of dredging Sediments and their Use in public works is increasingly prospected by Researchers in recent Years. Moreover, Floods in Kashmir valley in September 2014 compelled the Govt. Of Jammu and Kashmir to take Necessary steps in order to avoid similar situation in near future. This project therefore intends to study the stabilization of dredged material procured from Sindh Nallah having a higher content of alluvial Soil using Surkhi/Brick dust as an additive. Soil stabilization by this means can be utilized on airport pavements, highway pavements, earthen dams and many other situations where sub-soils are not suitable for construction. Keywords: Sindh Nallah, Dredged material, Surkhi, OMC, MDD, CBR, Direct Shear test.

Technical Proposal for Monitoring Thermal and Mechanical Stresses of a Runway Pavement

Airport pavements should ensure regular and safe movements during their service life; the management body has to monitor the functional and structural characteristics, and schedule maintenance work, balancing the often conflicting goals of safety, economic and technical issues. This paper presents a remote monitoring system to evaluate the structural performance of a runway composed of concrete thresholds and a flexible central runway. Thermometers, strain gauges, and pressure cells will be embedded at different depths to continuously monitor the pavement’s response to traffic and environmental loads. An innovative system allows data acquisition and processing with specific calculation models, in order to inform the infrastructure manager, in real time, about the actual conditions of the pavement. In this way, the authors aim to develop a system that provides useful information for the correct implementation of an airport pavement management system (APMS) based on real-life data. Indeed, it permits comprehensive monitoring functions to be performed, based on the embedded sensing network.

Estimating the Potential of Skid Incident at Airport Runway – A Case Study

Skid resistance or friction on airport pavement plays an essential role in runway safety to ensure safe stopping distance. It also provides safety margins during take off and landing of aircraft especially in directional control by reducing the occurrence of overrun and veer-off incidents. The friction between pavement and tire is related to multiple factors such as pavement surface characteristics (microtexture and macrotexture), material intruded between tire and pavement surface (water, snow, and contaminants), tire conditions (types, wear, and inflation pressure), and vehicle operating conditions (vehicle speed and whether the wheel is rolling or locked). Skid incidents due to wet pavement surface at airport runway is a major concern especially in regions of wet-tropical climate countries such as Malaysia. Thus, this study was undertaken to measure the potential of skid incident at airport runway by collecting data on pavement surface characteristics. Field data collection on pavement surface microtexture was conducted using the British Pendulum Tester at a local airport runway to obtain data for the estimation of the skid number (SN). Due to constraints, pavement surface macrotexture test was unable to be conducted at site. However, the pavement surface macrotexture was able to be estimated based on previous research. The potential of the skid incident was estimated by calculating the SN using the aircraft’s touch down speed at the airport runway, varies from 50 to 70 knots (57.5 – 80.6 mph or 92.6 – 129.6 km/h). The results of the estimation indicated that the possibility of the skid incident occurrence was high. This study provides useful insights for airport authority to investigate the potential of overrun and veer-off incidents of aircraft at the airport runway.

Ice pressure and icing volume expansion rate of acetate-based deicers under freezing conditions

Acetate-based deicers are frequently used as airport pavement de-icing fluids in cold regions. In this study, the ice pressure (Ip), icing volume expansion rate (ΔVP), freezing point (T0), and undercooling degree of acetate-based deicers were investigated. The above mentioned indices were also compared with that of water and NaCl deicers. The results showed that the cooling process and ice crystal growing process of acetate-based deicers could be divided into five stages. Additionally, the stabilised values of Ip and ΔVP decreased with the deicer concentration increases. Furthermore, the impulse concept of ice pressure (IPI) was proposed to evaluate the frost damage of concrete caused by deicers. The Ip, ΔVP , and T0 values of calcium magnesium acetate (CMA) deicer with different Ca/Mg mole ratios (i.e. 1/1, 0.91, 7/3, and 3/7) were tested in the ice pressure test. The value of CMA deicer with 3/7 Ca/Mg mole ratio was the lowest. However, the Ip values of CMA deicers with 0.91 Ca/Mg and 1/1 Ca/Mg mole ratios were the highest. Among all the tested acetate-based deicers, CMA deicers had the lowest values of Ip, ΔVP, and IPI. Moreover, the CMA deicer with 3Ca/7Mg mole ratio was recommended for deicing airport pavements to reduce the concrete frost deterioration caused by acetate-based deicers. In this study, we investigated the physical properties of acetate-based deicers, quantitatively analysed the destructive power of deicers in a freeze–thaw test, and studied the cause of freeze–thaw deterioration of concrete. Overall, this study provides a theoretical method for exploring new deicers.

3D Visualization of Airport Pavement Quality Based on BIM and WebGL Integration

AbstractBuilding information modeling (BIM) is well-known for improving the efficiency of the Architecture, Engineering, and Construction (AEC) industries. Currently, the support for web displays u...

Dynamic response analysis of airport pavements during aircraft taxiing for evaluating pavement bearing capacity

Dynamic response analysis of airport pavements during aircraft taxiing for evaluating pavement bearing capacity

Monitor Activity for the Implementation of a Pavement—Management System at Cagliari Airport

The conditions of airport movement-area pavements play a primary role on safety and regularity of airport operations; for this reason, the aerodrome operator needs to periodically survey their condition and provide their maintenance and rehabilitation in order to ensure the required operational characteristics. To meet these needs efficiently and effectively, the Airport Pavement-Management System (APMS) has proved to be a strategic tool to support decisions, aimed at defining a technically and economically sustainable management plan. This paper aims to investigate the theoretical elements and structure of the APMS; the appropriate methodologies to guarantee a constant updating of the system in all its aspects are presented, focusing on the specific case study of a medium-dimension Italian airport. The article describes the methods and the equipment used for the high-performance surveys and the condition indexes used for collecting and analyzing the data implemented to populate the APMS of Cagliari airport. Two major survey campaigns were carried out: the first in 2016 and the second in 2019. Both surveys were carried out using the same subdivision into sample units, following the ASTM D5340-12 criteria, to correctly compare data collected in different years. In order to sufficiently populate the APMS database, the measured and back-calculated data were stored and integrated using daily acquired pavement reports since 2009 and stored with the specific intention to develop customized decay curves for Cagliari Airport pavements. Preliminary results on the sustainable use of the APMS were reported even with data collected in a limited period and successfully applied to runway flexible pavement.

A prediction model of the coefficient of friction for runway using artificial neural network

Runway surface conditions are fundamental to ensure safety during landing and takeoff operations of aircrafts. In this manner, airport operators are required to monitor the coefficient of friction and macrotexture of runways to maintain its safety and plan maintenance and rehabilitation strategies when appropriate, since both these parameters get deteriorated with time. Thus, to assist aerodrome operators and regulatory agencies in the decision-making process for conservation and monitoring of airfield pavements, this study aimed to develop a prediction model for runway friction using Artificial Neural Network. Our results were satisfactory and may contribute to the decision-making process in the context of the Airport Pavement Management System.

A method for calculating and evaluating user costs in airport pavement management systems

An efficient airport pavement management system is essential to judge current runway conditions and predict future runway conditions and support decisions. However, one of the limitations is insufficient scope for analysis of the infrastructure environment, particularly regarding loss of revenue due to the need for total or partial closure of the runway in life-cycle cost analysis (LCCA) approaches. In this article, a method is presented for calculating indirect/user costs based on the net present value related to closed runway time in the cash flow variable. This method integrates passenger demand forecasts based on machine learning and the net operating revenue of an airport. Relying on a case study of Brasília International Airport, the consideration of a variable called the ‘equivalent operational susceptibility area’ improved understanding of the financial impacts on indirect/user costs and direct/owner costs. This variable enabled visualisation of the conditions for the financial feasibility of pavement intervention scenarios. The proposed method uses the required time of runway closure and the area to be maintained as balance weights between the direct and indirect costs of LCCA. Therefore, it is not reasonable to relegate indirect/user costs to estimated values or aircraft and passenger movement fees.

Testing Sentinel-1 SAR Interferometry Data for Airport Runway Monitoring: A Geostatistical Analysis.

Multi-Temporal Interferometric Synthetic Aperture Radar (MT-InSAR) techniques are gaining momentum in the assessment and health monitoring of infrastructure assets. Amongst others, the Persistent Scatterers Interferometry (PSI) technique has proven to be viable for the long-term evaluation of ground scatterers. However, its effectiveness as a routine tool for certain critical application areas, such as the assessment of millimetre-scale differential displacements in airport runways, is still debated. This research aims to demonstrate the viability of using medium-resolution Copernicus ESA Sentinel-1A (C-Band) SAR products and their contribution to improve current maintenance strategies in case of localised foundation settlements in airport runways. To this purpose, “Runway n.3” of the “Leonardo Da Vinci International Airport” in Fiumicino, Rome, Italy was investigated as an explanatory case study, in view of historical geotechnical settlements affecting the runway area. In this context, a geostatistical study is developed for the exploratory spatial data analysis and the interpolation of the Sentinel-1A SAR data. The geostatistical analysis provided ample information on the spatial continuity of the Sentinel 1 data in comparison with the high-resolution COSMO-SkyMed data and the ground-based topographic levelling data. Furthermore, a comparison between the PSI outcomes from the Sentinel-1A SAR data—interpolated through Ordinary Kriging—and the ground-truth topographic levelling data demonstrated the high accuracy of the Sentinel 1 data. This is proven by the high values of the correlation coefficient (r = 0.94), the multiple R-squared coefficient (R2 = 0.88) and the Slope value (0.96). The results of this study clearly support the effectiveness of using Sentinel-1A SAR data as a continuous and long-term routine monitoring tool for millimetre-scale displacements in airport runways, paving the way for the development of more efficient and sustainable maintenance strategies for inclusion in next generation Airport Pavement Management Systems (APMSs).

Proposal and Implementation of a Heliport Pavement Management System: Technical and Economic Comparison of Maintenance Strategies

Maintenance and rehabilitation (M&R) scheduling for airport pavement is supported by the scientific literature, while a specific tool for heliport pavements lacks. A heliport pavement management system (HPMS) allows the infrastructure manager to obtain benefits in technical and economic terms, as well as safety and efficiency, during the analyzed period. Structure and rationale of the APSM could be replicated and simplified to implement a HPMS because movements of rotary-wing aircrafts have less complexity than fixed-wing ones and have lower mechanical effects on the pavement. In this study, an innovative pavement condition index-based HPMS has been proposed and implemented to rigid and flexible surfaces of the airport of Vergiate (province of Varese, Italy), and two twenty-year M&R plans have been developed, where the results from reactive and proactive approaches have been compared to identify the best strategy in terms of costs and pavement level of service. The result obtained shows that although the loads and traffic of rotary-wing aircrafts are limited, the adoption of PMS is also necessary in the heliport environment.

A Machine Learning Approach to Determine Airport Asphalt Concrete Layer Moduli Using Heavy Weight Deflectometer Data

An integrated approach based on machine learning and data augmentation techniques has been developed in order to predict the stiffness modulus of the asphalt concrete layer of an airport runway, from data acquired with a heavy weight deflectometer (HWD). The predictive model relies on a shallow neural network (SNN) trained with the results of a backcalculation, by means of a data augmentation method and can produce estimations of the stiffness modulus even at runway points not yet sampled. The Bayesian regularization algorithm was used for training of the feedforward backpropagation SNN, and a k-fold cross-validation procedure was implemented for a fair performance evaluation. The testing phase result concerning the stiffness modulus prediction was characterized by a coefficient of correlation equal to 0.9864 demonstrating that the proposed neural approach is fully reliable for performance evaluation of airfield pavements or any other paved area. Such a performance prediction model can play a crucial role in airport pavement management systems (APMS), allowing the maintenance budget to be optimized.