t A group was formed at Sandia Corporation comprising corporation cmployces, onlisted personnel from the Army, Navy and Air Force, and college students, te obtain these Technical evaluation and procuroment or existing equipment was accom~ measurements, In some cases equipment had to be developed or existing equip- plished effectively. Installation and operation of the instrumentation equipment by the ment adapted, Sandia Group provided useful data from morc than 95% of the measurements planned, b. Large dependence was placed on the measurement of transient effects in- Blast pressures on the buildings, both volving a total of 1,065 gauge recordings, inside and outside, and comprehensive measurements of structural response were inde, Measure- Motion picture photography was used to record motions and modes of failure. ments were made of conditions of the buildings before and after boing subjected to blast, such as rod and transit surveys, audio velocity measurements in concrete, micrometer measurements of distances and natural period studics of ten structures, c. The Los Alamos Scientific Laboratory accomplished the still photography and the firm of Edgerton, Germeshausen and Gricr accomplished the motion picture photography. These photographic rocords will be of great value in analyzing struct- ural damage. &. CONCLUSIONS a The complete analysis of results will reauire several months since it is nceessary to take all the measured pressurcs and analyze cach structure to determine whether the deformitions caleuletod by the method cstablished prior to the tests checks out with the measured deformations. In the work which has been accomplished thus far very good agreemont, has becn obtained, ‘The measured pressures, howover, are quite different in many cases rrom those predicted by theory and shock tube experi- iments, It is in this Phe that the gre:test amount of effort is indicated, b. The shelter designs of the Corps of Engincers were proven adequate under heat conditions at a distance of 1700 feet fromtho tower, This distance was in- tended to provide the same peak pressure as for a point directly underneath the bomb at optimum height for a ten pound overpressurc. SOMG The conditions ef the test, particularly the effect of the ground, led to some uncertainty as to whether the she “yo 1 np id Shelt et ers did recci ve the same press* ure as would have beon experienced dircetly under~ neath the same bomb, From a general viewpoint, however, the test results will bo very uscful in indicating the order of value of the sheltor designs, c. o The analysis of models displayed in tho tests is incomplete, The use £ models toa investigate diffraction effe cts on structures appears promising * a at. 2 a" ad 7 + hoe daha Nentecioe nlp opm Peale ay sty eh loge MF eae de RIESETA pei poyv3 4 Meighur aleseek dep fg . . ao 4nay comme 2ipgu