CYCLIC STRENGTH OF UNDISTURBED SANDS FROM NIIGATA, JAPAN
Standard Penetration Tests, undisturbed field sampling, laboratory index property tests and laboratory cyclic triaxial strength tests were performed on cohesionless soils, to determine why some soil deposits failed by liquefaction while apparently similar deposits remained stable during the 1964 earthquake. Comparison of standard penetration test values, index property values, and cyclic triaxial strength values for soils from the two sites showed the following: (1) in situ relative density values were low at both sites ranging between 20 percent and 60 percent; (2) cyclic triaxial strength values for undisturbed soil specimens were not high. Cyclic stress ratios required to cause failure for 20 stress cycles were on the order of 0.2 for soil specimens at an average relative density of 62 percent and on the order of 0.14 for soil specimens at an average relative density of 33 percent; (3) sampling and testing at the river site showed low SPT values, low calculated relative density values, and low cyclic triaxial strength values. It was concluded that the river site, if unimproved, will show little resistance to liquefaction in future earthquakes; (4) it appears that the cyclic triaxial strength of specimens from large diameter samples and for specimens from Osterberg samples are reasonably equivalent when test results were compared at the same value of relative density; (5) SPT values and relative density values were slightly higher for the road site than for the river site. Nevertheless, soil at the river site liquefied and soil at the road site did not liquefy during the 1964 earthquake; it appears that most of the severe earthquake damage from liquefaction occurred in areas that were reclaimed by dumping sand through water; and (7) it became clear that any form of sampling, sample handling, or specimen preparation for relatively clean cohesionless soils weakens the soil by some amount. Therefore, the test results reported may be considered as a lower bound on expected field behavior of soils from Niigata.
U.S. Army Waterways Experiment Station3909 Halls Ferry Road
Vicksburg, MS USA 39180-6199
- SILVER, M L
- Publication Date: 1978-8
- Features: Figures; Photos; References; Tables;
- Pagination: 174 p.
- TRT Terms: Earthquakes; Field tests; Granular soils; Index tests; Laboratory tests; Liquefaction; Sand; Soil penetration test; Specific gravity; Strength of materials; Stress ratio; Structural analysis; Triaxial shear tests; Undisturbed samples
- Old TRIS Terms: Insitu methods; Liquefaction (Soil)
- Subject Areas: Geotechnology; Highways;
- Accession Number: 00184746
- Record Type: Publication
- Source Agency: U.S. Army Waterways Experiment Station
- Report/Paper Numbers: Tech Rpt S-78-10 Final Rpt.
- Contract Numbers: DACW39-76-M-2407
- Files: TRIS
- Created Date: Feb 3 1979 12:00AM