The assessment of the potential for an earthquake-induced loss of strength (liquefaction) of a granular deposit involves methods which are based on empirical observations, field and lab characterization data and associated analyses. These methods constitute an evolving state of knowledge/practice and involve systematic yet tedious data interpretation, reduction, correction and analysis. For one time/one point calculations these processes can be done by hand, yet they prove to be time consuming with the possibility of introducing unwanted errors at one or more of the many steps involved. The idea of relying on spreadsheets to address these shortcomings is not new. However, past efforts have included one method, with some cases ignoring effects of some important parameters or new methodologies to avoid the added complexity. The approach/tool developed and presented in this paper (LiqFactory 1.0) was motivated by, and developed and tested in the context of, a course on geotechnical earthquake engineering with the objective of presenting students with a platform for exploring and understanding the liquefaction phenomenon and the various state-of-the-practice tools available to assess it. The tool relies on standard penetration test (SPT) or cone penetration test (CPT) field test results, soil characteristic properties and earthquake data. Test specific corrections for various field parameters are applied along with other adjustments associated with soil characteristics/composition. In this paper, a concise technical background is presented followed by a thorough discussion of different methods used in programming the spreadsheet and resolving the many problems faced in developing it. In addition, the criteria used in programming the spreadsheets are presented, and finally an illustrative example application is provided to showcase the different features of the tool developed.

zLiqFactory v1.0.xlsm (272 kB)
Excel Spreadsheet associated with the paper