| Society of Exploration Geophysicists of Japan (SEGJ) has been developing an integrated geophysical method for non-invasive safety assessment of levees for 15 years. The method mainly consists of a surface wave method and a resistivity method. A cross-plot of S-wave velocity (Vs) and resistivity, obtained by the surface wave and methods respectively, is used for evaluating soil condition resistivity of levees. SEGJ organized a consortium to develop, evaluate, authorize, and standardize the method. The consortium conducted field investigations to evaluate the applicability of the methods, wrote up a guideline, defined a standard digital format of investigation results, developed a database. Total survey line length of and geophysical methods registered in the database is pproximately 700 km. Many levees were damaged by the Great East Japan Earthquake in 2011.The integrated geophysical method was applied to more than 160 km of damaged levees to evaluate their safety. This paper summarizes the development history, current situation, and road ahead of the integrated geophysical method. |
