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This report presents a decision framework for road management and planning at Eglin AFB, FL. The need for a road plan was denied in the Natural Resource Management Plan. The extent of the problem is enormous because Eglin has an extensive network consisting of approximately 1,500 miles of roads. Two interrelated problems exist: (1) costs of maintaining the roads, and (2) environmental impacts. The report focuses on the second issue. The sandy nature of the installation causes chronic maintenance as well as erosion problems. In addition, road material derived from borrow pits has economic and environmental costs. The unpaved roads and clay pits act as sources of sediment which may be transported into nearby streams. Sedimentation has potential adverse impact to wetlands and stream ecology. To address these problems, a road management workshop was held to offer solutions by reaching a consensus among the various road users. Synthesis of the workshop resulted in the following conclusions: (1) establish a road task force, (2) inventory the road system in terms of mission needs, traffic volume, maintenance conditions, and environmental concerns, (3) enter data into a geographical information system for automated decision making, (4) use weighted criteria to open or close roads, (5) adopt standards for open road construction and maintenance, (6) close roads either temporarily or permanently, and (7) annually review progress. Following these recommendations will result in reducing maintenance costs and minimizing environmental consequences of roads. (MM), Original contains color plates: All DTIC/NTIS reproductions will be in black and white.

A pavement evaluation procedure is presented for evaluating conventional flexible airfield pavements that will fail in fewer than 100 coverages. The procedure utilizes deflection data obtained from a Falling Weight Deflectometer and the age of the pavement to predict the coverages of an F-4 aircraft to failure. Procedures for correcting temperature of the asphalt pavement layer and for predicting performance of other aircraft are presented.

This study is the second phase of a two-phase program to develop a nondestructive pavement evaluation method to evaluate pavements designed to support aircraft with gross weights of less than 30,000 lb. A method that uses the deflection basin from nondestructive testing (NDT) to predict the elastic moduli of up to four pavement layers was developed. A computer program (CHEVDEF) was developed that predicts the moduli so that the deflection basin from a layered elastic solution approximates the measured basin. The nonlinear stress-dependent characteristics of the subgrade are defined. Moduli derived from NDT results are used in the PAVEVAL program developed in FAA-RD-77-186-I by R. A. Weiss to predict the allowable aircraft loads. The subgrade elastic moduli described by this method compares well with laboratory test results and with results from other methodologies. The predicted allowable load from this method compares well with the allowable load from the dynamic stiffness modulus procedure. Appendices present a laboratory procedure for determining the resilient modulus of subgrade soils, discuss the CHEVDEF program, and provide a guide to the use of the PAVEVAL computer program., See also Rept. no. FAA-RD-80-9, AD-A083 597 and Rept. no. FAA-RD-77-186-1, AD-A087 186.

Methodologies have been developed for nondestructive testing (NDT) and evaluation of air carrier airport pavements. This study, a two-phase program, addresses those pavements that are designed to support aircraft with gross weights of less than 30,000 lb. Phase I, reported herein, is to evaluate commercially available NDT devices with respect to operational characteristics, costs, transportability by cargo aircraft, accuracy, and reproducibility of measurements, and suitability for use in evaluating light aircraft pavements. The equipment evaluated included the Benkelman Beam, Dynaflect, Falling Weight Deflectometer, and Models 400, 510, and 2008 Road Raters. The WES 16-kip vibrator was used as a comparison device. Based on the evaluation parameters, the Dynaflect, Model 2008 Road Rater, and Falling Weight Deflectometer are evaluated applicable for testing light aircraft pavements. (Author)

This study evaluates experimental prefabricated membranes for use as expedient dustrpoofing and waterproofing mediums for current Army helicopters. Laboratory and skid tests were conducted on nine membrane candidates at the Waterways Experiment Station (WES) to select a medium-duty membrane that meets the Department of the Army approved Qualitative Materiel Requirement (QMR) for Prefabricated Airfield Surfacings. Skid tests determined the most critical helicopter with respect to locked-wheel braking or skid resistance., See also report dated Mar 70, AD-756 361.

The objective of this investigation was to design, construct, and evaluate two promising ALRS concepts for full-scale operations of the F-4 aircraft. After aircraft traffic was completed, test sections were trafficked to failure with loadcarts simulating maximum loaded F-4 and F-15 aircraft. Aircraft and pavement surface interaction were evaluated for a thin asphalt surfaced pavement and for unsurfaced stabilization soil pavement. Significant findings included: (1) an asphalt surface course thickness of 2 inches over a conventionally designed pavement will support 150 passes of the F-4 aircraft, (2) a surface course is required for stabilized soil structures, particularly in areas subjected to jet blast for the prevention of foreign object damage to engines, (3) deflection from the falling weight deflectometer can be used with a layered elastic model to predict performance of the pavement structures, and (4) the CBR design procedure should not be modified for the design of ALRS pavements.