Alternative Modified Binders for Airfield Pavements

摘要

The technical object of this research was to investigate materials, to modify, augment, extend and/or replace conventional asphalt cement binders for flexible airfield pavements, capable to sustain aircraft tire pressures of 350/400 psi. This study looked at a number of alternate materials and modified materials to determine their acceptability for producing the mixtures. There was a thorough review of the published literature concerning additive types, their effect on the properties of binders and mixers. Selection of a series of test procedures and development of a testing program to screen additives for their suitability for combination with bitumen, determine mix design procedures, and to measure the structural and mechanical properties of mixes was done. It may be concluded that aircraft fitted with vectored thrust can cause additional structural damage to pavements as a result of heating effects. It is also concluded that erosion is possible as a result of the blast from the vectored thrust. It is recommended that the operating parameters of aircraft using vectored thrust be investigated as this has considerable significance in relation to the damage potential. The analysis in this report provides sufficient data for a preliminary assessment of the probability of damage, therefore permitting a decision in relation to further investigation. Keywords: Additives, Modifiers, Asphalt, Creep, Stiffness, Rebound, Therman gradient, Vectored thrust. (sdw)