1. ERDC Knowledge Core
2. Pre - Engineer Research and Development Center (ERDC)
3. Soils and Pavements Laboratory - (8/1/1972 - 4/16/1978)
4. Technical Publication
5. Miscellaneous Paper

Title:	Summary of buckling and tension tests of landing mats as related to C-5A aircraft bow wave problems
Authors:	United States. Army Materiel Development and Readiness Command. Green, Hugh L. Smith, Carroll J.
Keywords:	Aircraft tires Landing mats Bow waves Seals Buckling Skid resistance C-5A aircraft Sliding friction Joints Junctions Waterproofing
Publisher:	Soils and Pavements Laboratory (U.S.) Engineer Research and Development Center (U.S.)
Description:	Miscellaneous Paper Abstract: In order to better understand and define the problems associated with the C-5A and landing mat, several investigations were conducted at the U. S. Army Engineer Waterways Experiment Station and Utah State University to study the characteristics of landing mats subjected to horizontal C-5A loads. Several mat configurations with various connector designs were evaluated in buckling, skid, joint slack, and traffic tests. Mats both with and without water seals were used in the tests; however, the heavy-duty truss web mat designs with their extra weight and additional strength were given primary consideration. In the buckling tests conducted, it was determined that panel width, mat unit weight, and formation width were factors which affect the buckling load of a mat system. The horizontal load at which buckling occurs depends almost exclusively on the vertical eccentricities existing in the mat system at the time the load is applied. These eccentricities or irregularities could be initiated by the presence of warped panels, damaged joints, uneven subgrade, etc. It is concluded that the approximately square truss web mat design sustained a much higher load per foot of width prior to the development of a bow wave or buckling. Square mats without water seals give higher resistance to sliding between mat rows than mats with seals. However, membrane beneath mat provides a lower coefficient of friction which enhances mat sliding. During the normal placement of mat, there is free slack in the panel joints which, although necessary for contraction and expansion, contributes to potential runway movement. Based on the findings of this study and similar studies involving mats which appear capable of satisfying the C-5A aircraft requirements, it is recommended that the heavy-duty truss web mat, with inherent waterproofing and laid with the internal extrusions perpendicular to traffic and the male/female joint continuous and transverse to traffic, be developed for the C-5A. Improvements should be made to the square truss web mat and the mat field tested with the C-5A aircraft. The anchor restrictor should be tested further and also included in a field test. An end anchorage system should be developed and evaluated.
Rights:	Approved for public release; distribution is unlimited.
URI:	http://hdl.handle.net/11681/20890
Appears in Collections:	Miscellaneous Paper