29 May 2024

Finite Element, Petrographic, and Mechanical Analyses of Field-Cored Concrete Fairlead Beam Anchor Rods from Luke Air Force Base

Abstract: The fairlead beam is used to accomplish installation of the Barrier Arresting Kit 12 energy absorber for setback aircraft arresting system (AAS) installations at permanent operating facilities. Typical fairlead beams are affixed to a Portland cement concrete (PCC) foundation pad by a series of anchor assemblies made up of steel anchor rods set in grout inside galvanized pipe sleeves. US Air Force Civil Engineering Center (AFCEC) subject matter experts have identified a pattern of premature failures in these steel anchor assemblies when they are nondestructively inspected during AAS overhauls. The US Army Engineer Research and Development Center was tasked by AFCEC to investigate potential reasons for these premature failures. This report outlines methods and results of a finite element analysis of the anchorage, a visual and petrographic analysis of field-cored PCC anchor rods from Luke Air Force Base, and a mechanical analysis of specimens taken from the anchor rods within the PCC cores. Multiple modes of PCC distress were observed, and corrosion was evident in and around the anchor assemblies. Mechanical testing of specimens from the anchor rods indicated that an inferior grade of steel was used to fabricate these particular assemblies. Finally, observed deviations from design intention are discussed.

11 Aug 2020

PUBLICATION NOTICE: Development of Expedient Ultra-High Molecular Weight Aircraft Arresting System Panel Installation Procedures

Abstract: The US Army Engineer Research and Development Center conducted an evaluation of different procedures to install ultra-high molecular weight polyethylene panels beneath pendant-based aircraft arresting systems (AAS). Currently employed techniques were modified or new techniques were developed to increase productivity and installation accuracy, aid in system constructability, and reduce logistical concerns when compared to AAS requirements and pavement repair guidance. Procedures for both asphalt concrete and portland cement concrete surfaced runway pavement were evaluated. The field evaluation was conducted from July to August 2013 at the Silver Flag Training Site, Tyndall Air Force Base, FL. The evaluation consisted of timing various procedures using a six- to eight-man installation crew. Equipment and supplies currently in Air Force inventories were preferred, but outside items were not prohibited if performance gains could be achieved and the new items were deployable using typical military cargo aircraft. Required work tasks were organized and grouped together to efficiently complete the panel installation work within multiple short-term runway closure windows without any long-term closures greater than 12 hours to allow for aircraft operations during the installation process. This report summarizes the timed field trials and the pertinent conclusions based on the results. Recommendations for implementation including additional equipment, supplies, and personnel needs are provided.