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|Author:||Paul Ervin Curtis|
|Title:||Evaluation and Improvments to the Modular Ballistic Protection System Stand Alone (MBPS SA) Anchoring System|
|Department:||Civil and Environmental Engineering|
|Committee Chair:||Habib J. Dagher, P.E., Professor of Civil Engineering, Co-Advisor ; William G. Davids, P.E., Professor of Civil Engineering, Co-Advisor|
|Committee Members:||Melissa L. Maynard, Assistant Professor of Civil Engineering ; Edwin Nagy, P.E., Lecturer of Civil Engineering|
|Date of Defense:||2011|
The Modular Ballistic Protection System (MBPS) for stand-alone applications is the third generation ballistic protection system developed at the AEWC Advanced Structures & Composites Center. Previous systems are MBPS TEMPER for metal framed TEMPER tents and MBPS RW for rigid walled containerized housing units. MBPS Stand Alone (SA) consists of multiple 1.2 m by 1.8 m ballistic panels supported by a rear strut fixed with a side strap three quarters from the base of the panel. The rear strut and the front of the panel are anchored with 457 mm long 16 mm diameter steel tent stakes. The MBPS SA is essentially a free standing set of ballistic panels designed to be deployed around air beam tents or other difficult to conform to infrastructure, equipment or personnel requiring ballistic protection. MBPS SA performance requirements consist of ballistic mitigation, blast overpressure resistance, weathering, durability, and fire resistance. These criteria have been addressed in two preceding AEWC research theses (Goslin 2007; Tower 2009). The focus of this research is the evaluation of the MBPS SA system on hard-packed ground conditions. MBPS SA was blast tested in November 2009 and November 2010 for three hard-packed ground conditions to determine system response. The system was tested on hard-packed silty sand, poorly graded gravel with sand and sandy lean clay. The system performed well on the sandy lean clay and silty sand, passing U.S. Army standards. The system had poor performance on the poorly graded gravel with sand and was determined to be a failure by U.S. Army Standards. The findings showed that the poorly graded gravel with sand had a significantly higher average grain size (i.e., D50) to stake diameter ratio compared to the other two hard packed soils, which resulted in less soil-stake contact and a limited ability to create frictional resistance to pull-out. Positive system performance on the two other hard-packed soils resulted in the determination that the MBPS SA system performs well on hard-packed soils of a nature likely to be found in situ. The MBPS SA system is expected to perform within design blast mitigation and ballistic protection requirements on hard-packed soils, as long as the mean partical size, D50, is sufficiently smaller then the stake diameter.
Curtis, Paul Ervin, University of Maine, CEE2011-001