Geophysical investigation for the rehabilitation of a flood control embankment

摘要

To comply with recently published seismic regulations and environmental standards, existing dams and embankments have to be evaluated for safety control, in addition to standard maintenance and repair, which is common practice for aging structures. In either case, engineering geophysics is almost the only viable option for investigating these structures and the underlying soil as a whole. In this contribution, electrical and seismic surveys are performed on an outdated flood control embankment that is expected to be put into service again. Integration of DC resistivity results with those of various seismic prospecting methods (seismic refraction, cross-hole S-wave and P-wave tomography and surface wave analysis) is found to be successful for defining a clear physical representation of the entire structure. The low-strain elastic properties (from seismic speeds of propagation) as well as the geometrical characteristics of the internal core of the dam and of the foundation soil serve as guidance for the rehabilitation intervention.