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TERTIARY EFFECTS OF BLAST--DISPLACEMENT. Preliminary Report

Description: Measurements were made of the velocity and distance of translation of anthropomorphic dummies and equivalent spheres caused by blast winds. The primary technique for recording the movement of these ohjects was phototriangulation. The secondary technique (applicable to certain of the equivalent spheres) was to have the spheres impelled into missile traps. The resultant penetration provides a means for determining the velocity at the time of impact. Analysis of the results from both the primary and secondary techniques is expected to provide some of the irformation identified in the objective. (auth)
Date: September 1, 1957
Creator: Taborelli, R.V. & Bowen, I.G.
Partner: UNT Libraries Government Documents Department

SECONDARY MISSILES GENERATED BY NUCLEAR-PRODUCED BLAST WAVES

Description: The generation of secondary missiles by blast waves was investigated in Operation Plumbbob for three nuclear detonations with estimated yields of 11, 38, and 44.5 kt. A trapping technique was used to determine the impact velocities for 17,524 missiles (stones, glass fragments, spheres, and military debris or steel fragments) which occurred in open areas, houses, and an underground shelter with an open entryway. The equivalent ideal-wave peak overpressures computed from measured blast data for the open-area stations varied from 3.8 to 21 psi. Two houses and an underground shelter were located where the overpressures were 3.8 and 65 psi, respectively. The effect of hill-and-dale terrain on the production of missiles was investigated on one of the shots. Precursor effects were noted on two of the shots at stations near Ground Zero. Missile velocities measured at all stations except the underground shelter were compared with those computed by use of a model based on an ideal blast wave. An analytical procedure was presented by which translational velocities of nmn can be estimated using the measured velocities of spheres and stones. Total distances of displacement were measured for 145 stones that weighed up to 20 kg and for 1528 fragments from a concrete-block wall. (auth)
Date: February 1, 1962
Creator: Bowen, I.G.; Franklin, M.E.; Fletcher, E.R. & Albright, R.W.
Partner: UNT Libraries Government Documents Department

COMPARATIVE NUCLEAR EFFECTS OF BIOMEDICAL INTEREST

Description: Selected physical and biological data bearing upon the environmental variations created by nuclear explosions are presented. Emphasis is placed upon the early consequences of exposure to blast, thermal radiation, and ionizing radiation to elucidate the comparative ranges of the major effects as they vary with explosive yield and as they brief definitions of the terminology employed is followed by a section that utilizes text and tabular material to set forth events that follow nuclear explosions and the varied responses of exposed physical and biological materials. Finally, selected quantitative weapons-effects data in graphic and tabular form are presented over a wide range of explosive yields to show the relative distances from Ground Zero affected by significant levels of blast overpressures, thermal fluxes, and initial and residual penetrating ionizing radiations. However, only the early rather than the late effects of the latter are considered. 52 references. (auth)
Date: September 1, 1960
Creator: White, C.S.; Bowen, I.G.; Richmond, D.R. & Corsbie, R.L.
Partner: UNT Libraries Government Documents Department

A MODEL DESIGNED TO PREDICT THE MOTION OF OBJECTS TRANSLATED BY CLASSICAL BLAST WAVES

Description: BS>A theoretical model was developed for the purpose of predicting the motion of objects translated by winds associated with "classical" blast waves produced by explosions. Among the factors omitted from the model for the sake of simplicity were gravity and the friction that may occur between the displaced object and the surface upon which it iritially rested. Numerical solutions were obtained (up to the time when maximum missile velocity occurs) in terms of dimensionless quantities to facilitate application to specific blast situations. The results were computed within arbitrarily chosen limits for blast waves with shock strengths from 0.068 to 1.7 atm (1 to 25 psi at sea level) for displaced objects with aerodynamic characteristics ranging from those of a human being to those of 10-mg stones and for weapon yields at least as small as 1 kt or as large- as 20 Mt. (auth)
Date: January 1, 1961
Creator: Bowen, I.G.; Albright, R.W.; Fletcher, E.R. & White, C.S.
Partner: UNT Libraries Government Documents Department

THE ENVIRONMENTAL MEDICAL ASPECTS OF NUCLEAR BLAST. Technical Progress Report

Description: The nature of certain critical lesions seen after exposure to air blast is described. The early lethality characterizing primary and tertiary blast damage is emphasized along with the seriousness of injuries caused by blastenergized debris. Tentative criteria are developed to the end that different levels of environmental variations caused by blast phenomena could be quantitatively related to various levels of biological response. Using the free- field scaling laws and a mathematical model whereby translational velocities can be computed for animate and inanimate objects, the criteria are applied to nuclear explosions ranging in yield from 1 kt to 100 Mt. Thus, it is possible to specify, as a function of yield, the hazard ranges inside which various blast injuries might occur. At these ranges the associated levels of initial nuclear and thermal radiation were computed to allow at least some assessment of the relative importance of all the major hazards from nuclear detonations. (auth)
Date: November 1, 1962
Creator: White, C.S.; Bowen, I.G. & Richmond, D.R.
Partner: UNT Libraries Government Documents Department

TERTIARY EFFECTS OF BLAST--DISPLACEMENT

Description: Thc objective of the project was to determine the velocity-time and distance-time histories of anthropomorphic dummies and equivalent spheres (idealized models having an acceleration coefficient alpha equal to that of the dummy) displaced by blast winds. The dummies and spheres were located at stations within regions of about 5 and 7 psi overpressures. The technique used for recording the movement of these objects was phototriangulation. Analysis of the films obtained gave the ond shot the field of veiw was obscured by smoke (perhaps dust too) before any motion could be recorded by the cameras. In one phase of the experiment, equivalent spheres were caught in flight at near predicted maximum velocity by missile traps. The depth of sphere penetration in the calibrated capture medium was then used to compute the sphere velocity. (auth)
Date: February 1, 1959
Creator: Taborelli, R.V.; Bowen, I.G. & Fletcher, E.R.
Partner: UNT Libraries Government Documents Department

TRANSLATIONAL EFFECTS OF AIR BLAST FROM HIGH EXPLOSIVES. Technical Progress Report

Description: A computational model was used in studies of the biological effects of blast from nuclear explosions. The translational effects of blast waves for objects as small as a 10-mg stone and as large as a 168-lb man were computed from theoretical studies and results were compared to field data for near-ideal blast waves from nuclear explosions. Results indicate that the motion of experimental objects can be satisfactorily predicted for free-field conditions or for window glass in houses. Results were computed for high explosives with free air burst. Parameters computed include velocity, displacement, and acceleration as functions of time for a variety of objects exposed to blast waves with 12 maximum overpressures ranging from 1 to 20 atm. All computations were made for one ton of high explosives burst in free air, but the results may be readily scaled to lower or higher yields and to surface bursts. The missiles are identified by their acceleration coefficients which range from 0.01 to 6.0 ft/sup 2//lb. (C.H.)
Date: November 1, 1962
Creator: Bowen, I.G.; Woodworth, P.B.; Franklin, M.E. & White, C.S.
Partner: UNT Libraries Government Documents Department

Comparative nuclear effects of biomedical interest. Civil effects study

Description: Selected physical and biological data bearing upon the environmental variations created by nuclear explosions are presented in simplified form. Emphasis is placed upon the ``early`` consequences of exposure to blast, thermal radiation, and ionizing radiation to elucidate the comparative ranges of the major effects as they vary with explosive yield and as they contribute to the total hazard to man. A section containing brief definitions of the terminology employed is followed by a section that utilizes text and tabular material to set forth events that follow nuclear explosions and the varied responses of exposed physical and biological materials. Finally, selected quantitative weapons-effects data in graphic and tabular form are presented over a wide range of explosive yields to show the relative distances from Ground Zero affected by significant levels of blast overpressures, thermal fluxes, and initial and residual penetrating ionizing radiations. However, only the ``early`` rather than the ``late`` effects of the latter are considered.
Date: January 12, 1961
Creator: White, C.S.; Bowen, I.G.; Richmond, D.R. & Corsbie, R.L.
Partner: UNT Libraries Government Documents Department

TERTIARY BLAST EFFECTS: THE EFFECTS OF IMPACT ON MICE, RATS, GUINEA PIGS AND RABBITS. Technical Progress Report

Description: A total of 455 mlce, rats, gulnea plgs, and rabbits was subjected to lmpact at velocitles ranglng between 25 ft/sec and 51 ft/sec. The deslred velocities were generated by allowlng the anlmals to free-fall from various helghts to a flat concrete pad. The ventral surface of each anlmal was the area of impact. Problt analyses of the 24-hr mortallty data ylelded LD/sub 50/ lmpact veloclties with 95% confldence limits as follows: mouse, 39.4 (37.4 to 42.0) ft/ sec; rat, ft/sec; and rabbit, 31.7 (30.2 to 33.3) ft/sec. The LD/sub 50/ figures for the mouse and rat were slgnificantly higher, statlstically, than those for the gulnea plg and rabblt. The small spread ln the LD/sub 50/ values suggested little variation ln the tolerance of blologlcal systems to impact. Further, the steepness of the mortallty curves lndicated a narrow survlval range to lmpact. Extrapolatlon of the experimental data to the 70 kg anlmal yielded a predicted LD/ sub 50/ impact velocity of 26 ft/sec (18 mph). Literature relevant to the human case was revlewed and the tentative appllcabllity of the predlcted flgures to adult man ls discussed. (auth)
Date: February 28, 1961
Creator: Richmond, D.R.; Bowen, I.G. & White, C.S.
Partner: UNT Libraries Government Documents Department

DETERMINATION OF AERODYNAMIC DRAG PARAMETERS OF SMALL IRREGULAR OBJECTS BY MEANS OF DROP TESTS

Description: Drag coefficients were determined for various irregular objects such as glass fragments, stones, steel fragments, and spheres by means of drop tests for use in a mathematical model to correlate nuclear explosion blast experiments. Drop tests were also made on small laboratory animals and extrapolated to estimate the drag properties of man. A method was developed to estimate the average drag properties of man from his total surface area. (D.L.C.)
Date: June 1, 1960
Creator: Fletcher, E.R.; Albright, R.W.; Goldizen, V.C. & Bowen, I.G.
Partner: UNT Libraries Government Documents Department

MISSILE STUDIES WITH A BIOLOGICAL TARGET

Description: Fourteen dogs located on the lee side of planted gravel, of a concrete- block wall, and of glass mounted in the open and in houses were exposed to the environmental variations associated with full-scale nuclear detonations. Aluminum foil was used to protect the animals from thermal effects. The missile environment was monitored through the use of quantitutive missile-trapping techniques. Pressure-time variations in the environment were also recorded. Biologic damage from overpressure and missiles was determined, and the associations between physical envtronmental factors and biologic response were noted and analyzed. The feasibility of utilizing ninssile data, along with other available information from the literature, as a means of quantitutively assesing biologic hazard was estublished by the close correspondence between observed and predicted dangerous wounds. This test provided full-scale validation of procedures and experimsnts worked out chiefly in the laboratory. (auth)
Date: April 1, 1960
Creator: Goldizen, V.C.; Richmond, D.R.; Chiffelle, T.L.; Bowen, I.G. & White, C.S.
Partner: UNT Libraries Government Documents Department

NUCLEAR BOMB EFFECTS COMPUTER, (INCLUDING SLIDE-RULE DESIGN AND CURVE FITS FOR WEAPONS EFFECTS)

Description: S>Based on data from the 1962 edition of The Effects of Nuclear Weapons, a circular slide rule was designed to evaluate 28 different effects of nuclear weapons. Of these 28 different effects, 13 relate to blast, 5 to thermal radiation, 1 to initial nuclear radiation, 2 to early fallout, 6 to crater dimensions, and 1 to fireball dimensions. Most of the parameters are presented as functions of range and yield (1 kt to 20 Mt). Techniques are described which make it possible to estimate most of the effects parameters for yields greater than 20 Mt or smaller than 1 kt. The report presents curve fits of weapons- effects data, design analysis for the slide rule, and instructions for use of the rule along with some of the implications of the data in regard to biological and structural damage. The machine techniques are mentioned which were used to prepare the original graphs necessary for the production of the slide rule. (auth)
Date: April 1, 1962
Creator: Fletcher, E.R.; Albright, R.W.; Perret, R.F.D.; Franklin, M.E.; Bowen, I.G. & White, C.S.
Partner: UNT Libraries Government Documents Department

BIOLOGICAL EFFECTS OF PRESSURE PHENOMENA OCCURRING INSIDE PROTECTIVE SHELTERS FOLLOWING A NUCLEAR DETONATION

Description: In two series of experiments 277 experimental animals, including 66 dogs, 52 rabbits, 52 guinea pigs, 63 rats, and 44 mice, were exposed under selected conditions in six different general types of instrumented above- and belowground shelters to blast produced by nuclear explosions. The distance of the several structures from Ground Zero ranged from 1050 to 5500 ft. The most severe alterations in the pressure environment occurring inside the structures followed the detonation of a nuclear device with a yield approximately 50% greater than nominal. The highest overpressure to which animals were exposed was 85.8 psi, the rise time of which was 4 msec. The overpressure endured for about 570 msec. Overpressures ranged from this maximum downward in 15 other exposure situations to a minimum of 1.3 psi enduring for nearly 1346 msec but rising to a maximum in about 420 msec. The latter pressure occurred inside a reinforced concrete bathroom shelter, which was the only surviving part of a house otherwise totally destroyed, at 4700 ft where the outside incident pressure was about 5 psi. Following the nuclear explosions, all animals were recovered, examined, sacrificed, and subjected to gross and microscopic pathological study. All lesions were tabulated and described. The results of pressure-time data, documenting the variations on the pressure environment, are presented and analyzed, and an exploratory attempt is made to relate the alterations in the pressure environment to the associated pathology observed. A critical review of selected material from the blast and related literature is presented. All data are discussed, and the several problems related to the design and construction of protective shelters are noted and briefly, but analytically, assessed. The most outstanding contribution of the field experiments and the related study of the literature was the unequivocal demonstration that the provision of adequate protective structures can ...
Date: October 1, 1956
Creator: White, C.S.; Chiffelle, T.L.; Richmond, D.R.; Lockyear, W.H.; Bowen, I.G.; Goldizen, V.C. et al.
Partner: UNT Libraries Government Documents Department

BLAST BIOLOGY--A STUDY OF THE PRIMARY AND TERTIARY EFFECTS OF BLAST IN OPEN UNDERGROUND PROTECTIVE SHELTERS

Description: Dogs, pigs, rabbits, guinea pigs, and mice were exposed to nuclear detonatiors in two open underground pantitioned shelters. The shelters were of similar constructions and each was exposed to separate detonations. Each inner chamber filled through its own orifice; thus four separate pressure enviromments were obtained. An aerodynamic mound was placed over the escape hatch of each structure to determine its effect on the pressurecurve shape inside the chamber. In one test a sieve plate bolted across the top of the mound was evaluated. Wind protective baffles of solid plate and of heavy wire screen were installed in the shelters to compare primary and tertiary blast effects on dogs. The shelters also contained static and dynamic pressure gages, radiation detectors, telemetering devices, and, in one test, air-temperature measuring instruments, dustcollecting trays, and eight pigs for the biological assessment of thermal effects. One dog was severely injured from tertiary blast effects associated with a maximal dynamic pressure (Q) of 10.5 psi, and one was undamaged with a maximal Q of 2 psi. Primary blast effects resulting from peak overpressures of 30.3, 25.5, 9.5. and 4.1 psi were minimal. The mortality was 19 per cent of the mice exposed to a peak pressure of 30.3 psi and 5 and 3 per cent of the guinea pigs and mice exposed to a peak pressure of 25.5 psi. Many of the rabbits, guinea pigs, and mice sustained slight lung hemorrhages at maximum pressures of 25.5 and 30.3 psi. Eardrum perforation data for all species, except mice, were recorded. Following shot 2, thermal effects were noted. Animals of the groups saved for observation have died from ionizing-radiation effects. (auth)
Date: February 1, 1959
Creator: Ricmond, D.R.; Taborelli, R.V.; Bowen, I.G.; Chiffelle, T.L.; Hirsch, F.G.; Longwell, B.B. et al.
Partner: UNT Libraries Government Documents Department