Evaluation of the static and cyclic strength properties of calcareous sand using cone penetrometer tests

Recent recognition of the seismic activity within the Hawaiian Islands Pacific by the engineering community has forced a reevaluation of the hazards that earthquakes pose to the populated coastlines of volcanic islands throughout the tropics. The potential risk of damage and loss of life is such that seismic levels assigned by the UBC and ICBO have been upgraded dramatically.; The use of cone penetration testing to analyze the behavioral properties, particularly liquefaction potential, of natural deposits is rapidly gaining popularity around the world. Extensive research in this area provides the geotechnical community with fairly reliable correlations between cone tip resistances and static and cyclic strength. However, current practice in evaluating the behavioral properties of a sand deposit involves the use of correlations developed for silica or terrigenous deposits. Tropical and sub-tropical areas often contain significant deposits of calcareous sediments, which behave differently from their terrigenous counterparts. Natural aging (cementation) of calcareous particles further complicates the behavioral properties of this soil type.; This thesis describes a research program aimed at developing cone tip resistance correlations for calcareous sand. The results of triaxial static and cyclic strength tests in conjunction with cone penetrometer testing in a specialty designed calibration chamber were compared against results obtained for a silica sand of similar gradation. The University of Hawaii Calibration Chamber Facility was developed specifically for this research effort with the support of the Hawaii State Department of Transportation and Federal Highways Administration.; The results indicate that penetration resistance in the silica sand is typically 1.5 to 2 times greater than that observed in the calcareous sand for specimens prepared with similar gradations and at similar relative densities. Static and cyclic strengths in the calcareous sand were greater than that of the silica. Aging effects typically increased the cyclic strengths and penetration resistance of the calcareous sand; however, static strengths appeared relatively unaffected.