Accession Number : AD0708010

Title :   RESPONSE OF BURIED CYLINDERS IN THE NEAR-CRATER REGION.

Descriptive Note : Final rept. Feb 67-Apr 69,

Corporate Author : NAVAL CIVIL ENGINEERING LAB PORT HUENEME CALIF

Personal Author(s) : Allgood,J. R. ; Lew,T. K. ; Rail,R. D.

Report Date : MAY 1970

Pagination or Media Count : 108

Abstract : Tests were performed in Operation Distant Plain, Event 6, on a 4-foot-diameter reinforced concrete cylinder and on three 9-inch-diameter cylinders to obtain information on the behavior of structures in the near-surface, high-overpressure region. All test structures were oriented with their longitudinal axes parallel to the surface and normal to a radius through ground zero. The data obtained were intended for use in checking the results of recently developed nonlinear computer codes. Thirty-nine of 45 channels of electronic instrumentation yielded data which provide information on the body motions and transmitted shock, the induced strains, and the interface pressures. Information on the failure mode of near-surface reinforced-concrete cylinders was obtained from observation of the small (9-inch-diameter) cylinders and from tests of similar cylinders in Operation Backfill. Induced stresses and accelerations were smaller than expected even though body motions of the order of 2 feet (vertical and horizontal) were experienced. The data clearly show the rapid attenuation of velocity by the soil; as a consequence of this attenuation, the effective stress on the large cylinder was only 20% of the peak surface pressure. This stress caused no visible damage to the large cylinder. However, two of the model cylinders collapsed and the other was badly cracked by the overthrusting that was peculiar to Event 6. (Author)

Descriptors :   (*NUCLEAR EXPLOSIONS, SURFACE BURST), (*UNDERGROUND STRUCTURES, REINFORCED CONCRETE), (*REINFORCED CONCRETE, *NUCLEAR EXPLOSION DAMAGE), SIMULATION, INSTRUMENTATION, DAMAGE ASSESSMENT, PRESSURE, VELOCITY, STRESSES, SOILS, EXPLOSIONS, INTERACTIONS

Subject Categories : Laminates and Composite Materials
      Structural Engineering and Building Technology

Distribution Statement : APPROVED FOR PUBLIC RELEASE