OPERATION HARDTACK. PROJECT 3.6. BEHAVIOR OF DEEP REINFORCED-CONCRETE SLABS IN HIGH-OVERPRESSURE REGIONS

Abstract : The primary objective was to determine the dynamic behavior of deep reinforced-concrete slabs in the overpressure region of 200 to 600 psi, and thereby to provide a basis for establishing design criteria for massive reinforced concrete structures under blast loads. Both one-way and two-way slabs placed flush with the ground surface were tested. The ratios of effective span to depth varied from 1.43 to 7.0. It was expected that, for slabs of these proportions, shearing strength would prove to be the controlling design parameter. Consequently, the test specimens were designed to study particularly shear strength of slabs both with and without shear reinforcement, though flexural strength was also considered. The slabs were tested during Shot Koa, and the weapon yield was given as about 1 Mt. As a result of foundation failures, no usable data was obtained on the response of the deep two-way slabs. Thus, no effort was made to evaluate current resistance criteria for these members. However, sufficient usable data was obtained on the one-way slabs to justify detailed analyses of those members.