MISERS BLUFF was a Defense Nuclear Agency test to determine the near simultaneous blast effects on the MX buried trench and multiple aim point basing concepts. It consisted of 7 tests of 120 ton at Misers Bluff at Planet Ranch in 1978, six of which were detonated simultaneously in MISERS BLUFF II.
Computational methods used to predict the response of structure targets, such as bridges and shallow-buried structures subjected to airblast from nuclear weapons, have been based in large part on well-established design procedures. These computations tend to produce conservative designs, however, the predicted response may be unconservative in a targeting problem. The lack of response data from tests on these types of structures in an airblast environment has prompted extensive test programs jointly sponsored by the Defense Nuclear Agency (DNA) and Office, Chief of Engineers. Three model bridge spans were tested in MISERS BLUFF, and a series of seven Foam REST tests were completed in the shallow-buried structures research program during the 1978-1980 period.
MISERS BLUFF II dust cloud data base was compiled of in-situ particle size spectral data and fallout data obtained during Phase 1 of the MISERS BLUFF II Cloud Sampling Program. The analysis indicated a mass loading ratio of about 7 at cloud stabilization (T+10 minutes) between the multiple and single burst dust clouds. Although, within the range of measurement uncertainties, this value may be comparable to that value of six predicted by linear superposition, photographic evidence of the multiple burst event strongly suggested this about 15 percent `enhancement` in mass aloft may be real. Of greater importance, the analysis revealed that linearly superimposing six of the MBII single burst dust clouds resulted in a significant overestimation of average mass concentrations that were found in the multiple burst cloud. This overestimation appeared to be due to the inability of linear superpostion to treat the effects of the hydrodynamic and thermodynamic interactions occurring between closely spaced detonations.
Lidar data was obtained at 1.06 and 0.53 micrometers during the MISERS BLUFF II-2 (MBII-2) tests at the Planet Test Site near Lake Havasu City, Arizona. Experiments were also performed at 10.6 micrometers, but data from these experiments were lost because the recording system malfunctioned. The results from the first four minutes after the detonation were obtained. In retrospect, the theoretical analysis, which was developed before the data was ready for final reduction, was of limited use because of the unexpected nature of the cloud echoes. The 2.5-MHz receiver bandwidth provided insufficient resolution for the signals that were returned from a region that extended at most only a few tens of meters into the cloud. For the most part, laser signals did not penetrate very deeply into the cloud. Average values for the volume backscattering coefficient have been calculated for the first two minutes after the detonation. In general, the results showed that lidar measurements provide little information about the formation of dust clouds as dense as that present at MBII-2. These measurements suggested that dust clouds produced by nuclear and large conventional explosions act as rough- surfaced solid objects in their effects on laser-based systems.
Troposcatter antennas were tested in the MISERS BLUFF operation to the Mast environment produced by a surface detonation of 120 tons of ANFO explosive. Twelve AN/TRA-37 antenna systems were exposed to the blast wave at various incident overpressure levels and orientations relative to the blast. These antennas consist of a ten foot diameter parabolic reflector dish suffered on the convex side with sixteen radial ribs and a pinned ended fifteen foot tubular mast secured to the ground by two sets of four cables. Two of the tested antennas were instrumented to measure pressure and strain time histories on the reflector dish and mast. These two antennas were located at the anticipated 2 psi incident overpressure level at head-on and tail-on orientations. The other antennas were placed at locations to receive various levels of damage.
For the pre-test calculations an analytical pressure model was developed for predicting the blastinduced loads on the circular parabolic reflector dishes as they encounter shock waves directly from the front and rear. The developed aerodynamic formulas express the time and spatial variations of the pressure loading and his time variation of the total force on the dish. The total force time history is applied to the top of the mast in a structural response model of the mast and nonlinear cable system. The stresses, strains and displacements of this mast model are determined using the NASTRAN computer code for pre-test calculations. The pressure time history was applied to shell models of the stiffened reflector dish using the PETROS 3.5 computer code for pretest calculations. The pre-test calculations indicate that at the 2 psi incident overpressure level the two antennas were in the region of threshold of permanent damage.
Various Department of Defense organizations used the Army standard medium tactical radio relay system for a variety of battlefield communication needs. The U.S. Army Ballistic Research Laboratory (BRL), in conjunction with the Army Engineer Waterways Experiment Station (WES), Agbabian Associates (AA), and the U.S. Army Electronic Research Development Command (ERADCOM), is conducting a research program to develop data and criteria for determining the vulnerability of this system to the effects of tactical nuclear and high-explosive weapons. The system, which was not designed to survive these threats, consists of electronic radio equipment, its protective shelter, and associated antennae. The system was subjected to large-scale high-explosive tests (events DICE THROW and MISERS BLUFF) and acceleration time histories were obtained at various points on the equipment racks containing the electronic gear.
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