Insitu Testing Methods Breakout Session Research Collaboration Field Testing Research Needs Ken Stokoe, Breakout Moderator

Research Collaboration Multi-method pre-event characterization of properties at likely liquefaction sites using body-wave, surface-wave, penetration testing and sampling. Identify potential investigation sites for pre-event characterization. Residual strength estimation for soils Site variability. Mechanism for improved funding of international non- conference research efforts. Collaboration on counter-measures against liquefaction.

Research Collaboration Utilize NEES/Japan/Taiwan funding organizations to facilitate international research collaboration, as opposed to workshop and conference support.

Field Testing ‘Out of the box’ thinking on new testing methods Pore Pressure Dissipation measurements at field sites to correlate with fines content. Vs procedure needs a critical review, and potentially comparison of lab and field measurements. Combining Vs with other methods (e.g. geophysical, penetration, EM, acoustic) to better characterize soil properties and texture.

Field Testing Thin layer versus global characterization of liquefiable deposits (e.g.. suspension logging vs SASW)

Research Needs Short rod energy correction for SPT Large particle characterization methods, and validity of extrapolating small particle correlations to large particle soils Better characterization of strength loss in liquefiable and strain-softening fine grained soils Performance based standards for ground modification to mitigate liquefaction effects. Uncertainty in empirical methods, parameters, models formulation, and how do we incorporate uncertainty into design procedures.

Research Needs Resolving influence of plastic versus non-plastic fines on liquefaction resistance of soils. New generation of tools to refine or replace the Chinese Criteria for identifying liquefaction prone soils based on investigations from recent earthquakes. Development of methods to predict consequences (strain potential) of liquefaction post-triggering. Better guidelines for what field conditions merit additional testing (e.g., Vane shear if FC > xx%)

Research Needs Better fines content and void ratio determination in-situ by indirect measurement (Visual, Geophysical, penetration, EM, acoustic).