Evaluation of mobile, composite airfield mat
Andrzej Leski, Mariusz Wesołowski, Michał Stefaniuk
Quarterly No. 4, 2012 pages 237-244
DOI:
keywords: mobile airfield mats, runway damage repair, composite mat, finite element method
abstract One of the basic requirements needed for proper aircraft operation in combat situations is the provision of an adequate number of airfields and a sufficient level of operational readiness. The rapid repair of airfield pavements enables quick resumption of air operations. The existing technology and methods of airfield pavement reconstruction could not meet the stringent time requirements of military operations, that is why mobile, composite airfield mats have been developed. In the paper, the operational and maintenance advantages of the elastic, mobile airfield mat ELP-1 KRATER manufactured by Stocznia Żuławy Sp. z o.o. are shown. The results of field and laboratory tests, performed by the Air Force Institute of Technology, Poland (ITWL) are also shown. The laboratory tests consisted of basic material property testing, as well as fatigue testing of the composite material. Strength tests of the mat-to-ground anchoring bolts were also performed, the results of which are presented in the paper. The field tests consisted of two stages: static and dynamic. In the static tests, the quality of the crater soil filling was tested with pressure plates and deflectometers. The dynamic testing had the form of several runs with a heavy truck on the mat-subbase system instrumented with strain gauges. These braking runs were an approximation of the loading conditions present during aircraft landing, and the weight of the test vehicle was comparable to the weight of transport aircraft. The overall levels of the recorded reaction forces were low, and the heaviest loading occurred during the most aggressive braking and turning maneuvers. The preliminary numerical model of the system consisting of the mat and the soil subbase is also presented. The numerical analysis was performed with the use of the Finite Element Method (FEM). A local model used to test the subbase stiffness was created alongside an associated global model which was employed to simulate the heavy test vehicle runs. The FE analysis has confirmed the theoretical assumptions and helped to put the experimental results in a proper framework. The overall evaluation proves that the mechanical strength of the composite mats is sufficient to withstand loads that may come from heavy military aircraft.