| Correlations between the shear wave velocity and void ratio, and the shear wave velocity and standard penetration resistance value are examined for saturated sandy soils which have been grouped according to the Unified Soil Classification System, and separated by geologic age; a correlation between the cyclic stress ratio causing liquefaction and normalized shear wave velocity has been developed using field data for a number of saturated sandy soils; the accuracy of shear wave velocity measurements taken using the seismic cone penetrometer is examined.; Correlations between shear wave velocity, V{dollar}sb{lcub}rm s{rcub}{dollar} and standard penetration resistance N-value, for obtaining in situ shear wave velocity estimates from standard penetration resistance values, all overestimate the shear wave velocity by approximately 25%. Nevertheless, the correlations may have potential for use in obtaining rough estimates of shear wave velocity for use in dynamic analyses. Correlations between shear wave velocity and standard penetration resistance value are independent of geologic age for silty sand, clayey sand, poorly graded sand with silt binder, well graded sand with silt binder, and low plasticity silt soil groups, however, the poorly graded sand group correlation is dependent on geologic age. Correlations between normalized shear wave velocity, V{dollar}sb{lcub}rm s1{rcub}{dollar}, and energy and depth corrected standard penetration resistance, (N{dollar}sb1)sb{lcub}60{rcub}{dollar}, yield the same results.; A proposed correlation between the cyclic stress ratio to cause liquefaction and the normalized shear wave velocity, which is suitable for soils ranging from silts to gravels, shows promise for use in liquefaction potential analyses. The effect of fines content on the cyclic stress ratio-normalized shear wave velocity correlation is to shift the boundary curve between potentially liquefiable soils and soils which are not likely to liquefy to the right. Therefore, correlations between cyclic stress ratio and shear wave velocity which include all soils will give conservative estimates of the liquefaction potential of clean sands.; Shear wave velocity measurements taken using the seismic cone penetrometer are capable of measuring shear wave velocities which are within 10% of the shear wave velocities obtained using synthetic seismograms when there are no changes in soil type, and no abrupt changes in the stiffness of the soil in adjacent layers. The synthetic seismogram shear wave velocities account for the effects of multiples, transmission, ghosts, reflections, refractions, and diffractions. These effects are important when the first arrival time of the shear wave cannot be deciphered clearly from a seismic wave trace. When the first arrival time is clear, the most important factor is refraction which is strongly affected by the source to receiver offset for the seismic cone penetration test.; When there is a change in stiffness of the soil as measured by the standard penetration resistance value, of greater than 10 blows/ft in adjacent soil layers, seismic cone shear wave velocities could be in error by {dollar}pm{dollar}10 to 25%.; When there is a change in the stiffness of the soil associated with a change in the soil type, seismic cone shear wave velocities measured at or near the interface where the soil type changes could be in error by approximately {dollar}pm{dollar}25% to 70%. (Abstract shortened by UMI.)... |
