CHAPTER 5.27 EFFECTS OF BLASTS ON STRUCTURES, PAVING, AND PIERS Information as to the observed design adequacy of structures may be valuable in future planning. For this reason, a tabulation follows of scientific structures used in the experiments, with observations on the apparent effects of blast. Descriptions of the structures are given in Chapters 5,11 and 5.12 of this volume. For the design of those structures intended to survive the experiments, probable blast pressures to which each would be exposed were furnished by J-Division, and in most cases these pressures controlled the design. However, in some cases, wall thicknesses were determined by the radiation shielding required. Design analysis showed in some cases that the anticipated blast pressures on structures at desired data points were so high that structures designed to survive would have been extremely costly. Inspection of all structures was made from June 16 to July 2, 1951 In general, the inspection indicated adequate design and a good quality construction. Comments which follow as to the adequacy of design relate only to the effect on structures themselves and not to their scientific purpose, DAMAGE TO SCIENTIFIC STRUCTURES Station 1 - 200 Foot and 300 Foot SteelTowers. These stations were expendable and were completely destroyed. Small quantities of tower steel were in evidence at the sites as were parts of the footings and anchors, station 2 —- Wood Frame Structures. These structures were com pletely expendable and were destroyed at all sites. Design was ade- quate for the purpose intended. Stations 3. 4, and 5 - Plywood Boxes Mounted on Four by Four Posts. These stations suffered various degrees of damage, but it is believed that they adequately served the purpose intended. Stations 6a and 6b - Reinforced Concrete Structure. The 6a struc- tures were Sandstone structures rehabilitated for Operation Greenhouse. These structures showed considerable cracking, but there was no evidence of structural failure, Station 6b structures showed slight vertical cracking (0.02 inches or less in width) and the design is tend continuously provide paths for 5-304 in the side walls. There was no evidence of failure, considered adequate. Cracks apparently did not exthrough the walls; and therefore probably did not radiation or dust.