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Using the same critical layers as selected for DCP testliquefaction evaluations, V S1 , CSR M7.5 , and CRR M7.5 wereaveraged over the critical depths for each test site profile. Theresults were plotted along with the Andrus and Stokoe (2000)CRR M7.5 curves in Figure 11B.DISCUSSIONAs shown in Figure 11, the liquefaction predictions made usingboth the DCP and SASW test data reasonably match fieldobservations. This is particularly significant for the DCP databecause a correlation was first required to convert the measuredN DCPT to SPT N-values (shown in Figure 5A), and undoubtedly,this correlation is inherently uncertain. Also, the DCPwas only able to test down to a depth of ~6 m at a maximumand usually less than about 4.5 m. Below this depth, N DCPTbecame large because of the presence of a dense layer and/orbecause of the increase in effective confining stress. Becausethe DCP is manually operated, performing tests beyond ~5 mdepths becomes very laborious even in relatively loose sanddeposits. The SASW test was able to test to deeper depths thatthe DCP, but was still limited to depths of ~6 to 9 m with thesledge hammer source. These depth limits are true shortcomingsof both tests because at a few DCP and SASW test sites,available cone penetration test (CPT) soundings indicated thepresence of potentially liquefiable layers deeper in the profiles.As a result, our selected critical layer may only be one of multiplecritical layers in the profile and may not be the most critical.Also from Figure 11, it can be noted that most of the DCPand SASW tests were performed at sites that liquefied, with apaucity of data from sites that did not liquefy. The reason forthis is the manifestation of liquefaction at the ground surfaceis a definite indication that liquefiable soils are present. Severalno-liquefaction sites were investigated, especially ones adjacentto sites that liquefied. However, in the majority of these caseswe were not able to find a sandy stratum below the groundwater table in the upper ~5 m of these sites using the handauger.As a result, DCP tests were not performed at these sites,and the sites were not included in the DCP database.CONCLUSIONSThe U.S. and New Zealand members of the GEER team performedDCP and SASW tests after the 4 September 2010 M w7.1 Darfield earthquake and the 22 February 2011 M w 6.2Christchurch earthquake. Both tests are relatively portable,making them suitable for rapid, post-earthquake investigations.Of particular interest to the team were characterizing sites thatliquefied during either one or both of the earthquakes. Usingthe in-situ test data in combination with estimated PGAs,the liquefaction potential at the test sites was evaluated andcompared with post-earthquake observations. Despite someshortcomings of the tests, they did a relatively good job in correctlypredicting the occurrence/non-occurrence of liquefaction,proving the value of these tests for rapid, post-earthquakeinvestigations.ACKNOWLEDGMENTSThe primary support for the US GEER Team memberswas provided by grants from the U.S. National ScienceFoundation (NSF) as part of the Geotechnical Extreme EventReconnaissance (GEER) Association activity through CMMI-00323914 and NSF RAPID grant CMMI-1137977. Also,Dr. Wotherspoon’s position at the University of Aucklandis funded by the Earthquake Commission (EQC). However,any opinions, findings, and conclusions or recommendationsexpressed in this material are those of the authors and do notnecessarily reflect the views of the National Science Foundationor the EQC.REFERENCESAbrahamson, N. A. and R. R. Youngs (1992). A stable algorithm forregression analyses using the random effects model. 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