ABSTRACT
This chapter is a review of some of the usual geophysical survey techniques applied in the assessment of civil engineering structures and infrastructures. The different techniques are based on the measurement of determined parameters and allow delineating the distribution of particular characteristics of the subsurface media. In this way, resistivity surveys allow to define the distribution of the resistivity in a volume of material; seismic and acoustic surveys provide the distribution of elastic parameters; GPR defines the boundaries between zones characterized by electromagnetic properties; a magnetic survey is capable of defining variations of the Earth’s magnetic field as a consequence of bodies embedded in the medium, characterized by different magnetic parameters; and gravimetric survey allows to determine the existence of inner targets that present different density than the surrounding materials.
