U.S. Army Engineer Research and Development Center’s APT Research Haley Bell Airfields and Pavements Branch Geotechnical and Structures Laboratory Vicksburg, Mississippi

Line-of-Communication Bridge Full-scale LOCB section 15 in. wide and 51 ft long Constructed over an open pit Evaluate surface durability of bridge deck B-52 tire loading to simulate tri-lateral bridge design code Channelized traffic in outer wheel path Target of 100,000 HVS-A passes

Line-of-Communication Bridge Failure in deck surface with B-52 tire Switched to dual tandem at ~36,000 passes

Next Generation ADR Backfill Materials Objective: To find suitable alternatives to rapid-setting flowable fill for backfill during the airfield damage repair process. The purpose is to rapidly stabilize locally available materials in place while requiring minimal compaction equipment. Goal: Repair solution to sustain at least 500 F-15E passes and up to 3,500 F-15E passes Mechanical Stabilization Chemical Stabilization

Foam Backfill Technology for RADR Rapid Airfield Damage Repair (RADR) Field demonstration with troop support Repaired simulated bomb craters using rigid polyurethane foam backfill with rapid-setting concrete caps In-house developed prototype foam dispensing equipment Repairs met objective of 3,500 F-15E passes Benefits to the Warfighter: 4,500 lb of foam backfill replaced 30,000 lb of soil fill Eliminated the need for compaction Resulted in 50% reduction in repair times compared to legacy techniques Repairs met RADR performance criteria

Other/Future APT Research Continued Geosynthetic Research Full-scale geocell test section Update DOD specifications Full-scale geogrid test section Military truck loads Laboratory “box” testing Benefits of geogrids in airfield pavements Next Generation Airfield Matting Systems RADR – continued performance of next generation materials Performance evaluation of cold in-place recycling Performance of non-traditional airfield pavements with low aircraft tire pressure Thin pavements and surface treatments Model validation - PCASE