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This study was undertaken to develop a new index, the Airport Runway Roughness Index (ARRI), that considers the effect of runway space when evaluating airport runway roughness. The difference between roadway and runway roughness evaluations is analysed in detail and the spatial effect is considered for a proposed runway roughness evaluation model. The evaluation of runway roughness should fully account for the dynamic responses of different typical aircraft during taxiing at the most unfavourable speed for the full cross-section of the runway. ARRI is defined according to the normalised weighted average of the vibration responses of typical aircraft models at the most unfavourable excitation waveband, the most unfavourable taxiing speed, and the most unfavourable lateral offset position within the longitudinal distance of the runway. Using runway three-dimensional full-section unevenness data collection equipment, a runway roughness evaluation procedure that is based on ARRI is proposed. The ARRI system provides qualitative improvement in terms of its representation ability, the rationality of the evaluation criteria, and the correlation of the indicators. [ABSTRACT FROM AUTHOR]

Airport runway roughness can be characterised by power spectral density (PSD) and two spectrum parameters, namely, the unevenness index and waviness. In order to find suitable spectrum parameters for airport runway roughness, seven runway profiles in China were measured to expand the current database of runway profiles. The statistical distributions of the spectrum parameters for runway roughness then were calculated, and the effects of the spectrum parameters on aircraft vibrations were analysed. The results show that the mode of the unevenness index is 0.13, which is a little lower than that of an A-level road, and the mode of waviness is 2.2, which is higher than the waviness recommended in ISO road classification. Moreover, as the unevenness index and the waviness increase, the aircraft vibrations become more severe. The aircraft vibration responses can be represented as a function of waviness, unevenness index, and speed, with a high correlation. At a constant speed, the relationship between the threshold values of the unevenness index and waviness can be shown as a straight line in a log plot. Finally, taking 200 km/h as the representative speed, threshold curves of the spectrum parameters, which are based on ride comfort levels and statistical analysis are proposed for the the simulation of aircraft vibration. [ABSTRACT FROM AUTHOR]

This study was undertaken to develop a new index, the Main Landing Gear Cumulative Stroke (MLGCS) index, to evaluate airport runway roughness. Using ADAMS/Aircraft software, we first developed and validated a virtual prototype model of the Boeing B737-800 aircraft and then employed the model to predict the aircraft's dynamic responses with regard to roughness. Using this prototype model and comparing it to the International Roughness Index (IRI) that is designed to evaluate roadway roughness, we established a landing gear cumulative stroke (LGCS) model to represent runway roughness. The results show that taxiing speed is an important factor using the LGCS model. According to the most unfavorable scenario, we determined the LGCS of the nose landing gear to be 100 km/h and that of the main landing gear to be 60 km/h. These results underscore that, based on correlation analysis, using the cumulative stroke of the main landing gear is more reasonable than using that of the nose landing gear to evaluate runway roughness. Furthermore, based on measured data for 37 runways, a comparison of commonly used roughness indices indicates that the MLGCS index proposed in this paper is superior to both the Boeing Bump Index and the IRI. [ABSTRACT FROM AUTHOR]

• Extreme value distribution better represents aircraft wheel wander. • The damage caused by each load repetition is considered individually. • The load transfer effect is taken into account using finite element analysis. • The proposed method typically produces smaller CDF values. This paper proposes an approach to determine cumulative damage factors (CDFs) based on Miner's law to improve airport runway rigid pavement design. The approach uses measured aircraft wheel wander data and constructed influence surfaces. In this study, we developed an aircraft wheel wander measuring system and measured actual aircraft wheel loading locations at the Shanghai Hongqiao International Airport (SHA). We constructed influence surfaces using finite element analysis (FEA) and multivariate interpolation. We conducted FEA of a nine-slab model to simulate load transfer effects. Based on the measured wheel wander distribution and the constructed influence surface, a cumulative damage surface construction approach for CDF determination is proposed. The preliminary benefits of the proposed cumulative damage surface method are that (1) the damage caused by each load repetition is considered individually for the CDF calculation and (2) the load transfer effect is taken into account using FEA simulations. Also, the field data we collected at SHA show that, compared to normal (uniform) distribution, extreme value distribution better represents aircraft wheel wander. A comparison between the CDFs calculated using normal distribution and extreme value distribution indicates that the maximum CDF is increased by 210% using extreme value distribution. According to the several cases analyzed in this study, the proposed cumulative damage surface method typically produces smaller CDF values than those calculated using the traditional Civil Aviation Administration of China method. Traditional airport runway rigid pavement design methods could be improved and optimized in terms of accuracy and performance using the proposed cumulative damage surface method for CDF determination. [ABSTRACT FROM AUTHOR]