| Detailed geophysical surveys were carried out on an embankment slope of a mountain road situated in cold region, near Sapporo, Hokkaido. The surveys purposed to demonstrate the capability of near surface geophysics for the delineation of 2D structure along road embankments. 2D and 3D resistivity measurements, hybrid surface wave survey, portable dynamic cone penetrometer testing, and pore water pressure monitoring were adopted for the surveys. We conducted the field measurements twice before the snow season in 2013, and just after the snowmelt season in 2014 when the slope surface had been scraped and protected with caged riprap. No obvious change was observed in the resistivity profiles along a reference line set outside the stabilized slope zone. In contrast, the resistivities distinctively increased in the groundwater discharged zone. Surface wave survey clearly delineated the deepening of embankment thickness at the surface seepage zone in the slope. In conclusion, small-scale complex structure in the embankment, which might cause irregular distribution in the slope stability, was clearly identified by means of the detailed geophysical survey. In addition, it was demonstrated that periodic measurement was useful to evaluate the effect of slope stabilization work. Read More: http://library.seg.org/doi/abs/10.1190/segj122015-077 |
