Accession Number:

ADA221320

Title:

Foundation Investigation for Ground Based Radar Project-Kwajalein Island, Marshall Islands

Descriptive Note:

Final rept.

Corporate Author:

ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS GEOTECHNICAL LAB

Personal Author(s):

Report Date:

1990-04-01

Pagination or Media Count:

70.0

Abstract:

Geophysical tests comprised of surface refraction and borehole seismic tests were performed. Results from geotechnical in situ tests, which included standard, penetration and plate bearing tests, are also presented to provide a comprehensive report on the foundation materials. The elastic properties, Youngs modulus, Poissons ratio, shear modulus, and constrained modulus were determined as a function of depth for the foundation soils. These properties are necessary to design a stable foundation that will experience dynamic loading. Foundation materials encountered at this site were coral sands, silts, and gravels to a depth of 60 ft el -52. The upper 14 ft of foundation soils are a hydraulically placed fill of beach sand. The materials are medium dense to dense sands. A global average SPT N sub 1 60 value of 22 is appropriate for the site and correlates to a sand with a relative density of 65. The shear modulus ranges from 77,000 psi. Poissons ratio varies from 0.40 for unsaturated to 0.49 for saturated soil. A method was presented to estimate moduli under the expected load from present unloaded in situ moduli values using the K2 parameter. An estimate of the moduli for the expected foundation load was presented for the upper 30 ft of the foundation. A comparison of the plate bearing test and seismic derived Youngs modulus shows good agreement, 123,000 psi and 78,000 psi, respectively. Radar tower foundations Dynamic loads Soil moduli.

Subject Categories:

  • Soil Mechanics
  • Structural Engineering and Building Technology

Distribution Statement:

APPROVED FOR PUBLIC RELEASE