Design, Analysis and Instrumentation of a Full-Scale Reusable Landmine Test Rig, 18-R8383
Carl E. Weiss
James T. Mathis
Inclusive Dates: 04/03/13 – 08/05/13
Background — SwRI has performed mine blast testing for a variety of clients over the past several years to support the development of mine blast-resistant vehicles. Tests have been performed on full-scale vehicles and on vehicle components. A majority of component tests have been performed on the SwRI Universal Landmine Test System (ULTS), a reusable fixture for repetitive testing with charges up to 12 pounds TNT. This project was conducted to meet client demands to test larger vehicle components without the need to fabricate the full vehicle and to do so with larger charges.
Approach — SwRI had indications that a client would pay for fixture fabrication if SwRI could design a fixture for full-scale testing and demonstrate through numerical simulations that it could survive repetitive testing with charges up to 60 pounds TNT. A quick-look project was used to meet client needs for testing in the fourth quarter of 2013. The test fixture needed weight and size goals to represent a full size vehicle, and strength and durability were overriding concerns. Discussions with existing clients led to a target size of 6 feet by 8 feet and a maximum weight of 32,000 pounds.
Accomplishments — CAD layouts were developed to size the fixture to accommodate a 6-foot by 8-foot test article. Early layouts indicated that the frame must be at least 7 foot by 9 foot in platform. If fabricated from a solid plate, ballast could be cut from the plate center to increase overall fixture weight. Although plates with thicknesses greater than 14 inches were considered for their bending strength and stiffness, a 14-inch plate gave fixture weights that were consistent with the weight goals of the project. A 14-inch thick, SA 516 Grade 70 steel plate, of adequate size, was located in stock. Numerical simulations were performed to demonstrate that a test fixture, cut from the SA 516 Grade 70 steel plate, was adequate to withstand the blast loading from a buried 60-pound TNT charge. The final configuration is shown below. It has been fabricated, and the first client-funded tests have been performed with the fixture.