Development of Passive High Pressure Gauges - Field Experiment.
Abstract
High pressure passive gauges capable of measuring peak shock pressures in the range of 2 to 25 kbar near detonating high explosives are being developed. The operation of these gauges is based upon the characteristics of second order transformations in pure metals or single crystals of alkaline halides and changes in the electrical characteristics of metal oxide varistors (MOV). This paper describes the results of an experiment in which three RbCl samples and four ZnO MOVs were placed against a 0.70-m thick concrete wall at the other side of which 2570 kg of explosives were detonated. The explosive and the concrete wall formed the driver end of a large shock tube. The tube and back of the wall were covered over with alluvium. At the gauge location, the alluvium depth was approximately 5 m. The samples were each located inside an individual pressure cell assembled into groups on steel plates to form gauges. The gauges were recovered some 2.5 m away from their original position. They had been translated and tumbled horizontally away from the burst point. The pressure cells were deformed and five out of seven samples were recovered--two MOVs and three RbCl. An examination of the RbCl samples indicated no phase change, meaning that the shock pressure appeared not to have reached the expected 12 kbar. The MOV samples were deformed, making the results of their reading of low confidence. Nevertheless, a tentative lower bound on the shock peak pressure can be placed at 9 kbar. The pressure cells suffered severe permanent deformation, leading to the conclusion that the dynamic stresses developed during their motion away from the burst point reached approximately 9 to 13 kbar. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 31, 1979
- Accession Number
- ADA077194
Entities
People
- Craig C. Hudson
- Jacques E. Schoutens
- Steven L. Senesac
Organizations
- General Electric