ISC'2 experimental site investigation and characterization - Part I: conventional and tomographic P and S waves refraction seismics vs. electrical resistivity

摘要

The in-situ investigation and characterization of ISC'2 experimental site comprised the application of several geophysical borehole and surface methods, namely P and S waves seismic cross-hole (CH), down-hole (DH), refraction, electrical resistivity, S waves high resolution shallow reflection, ground penetrating radar (GPR), as well as geotechnical tests, namely SPT, CPT, DMT, among others. The site, located within the campus of Faculty of Engineering of the University of Porto (FEUP), is geologically formed by an upper layer of heterogeneous residual granite soil overlaying rather weathered granite contacting a gneissic migmatite. Direct and indirect results from some of the referred surveys are compared between them and with some of the available geological and geotechnical information, in particular hereby (Part Ⅰ), those obtained from P and S waves conventional (RC) and tomographic (RT) refraction, CH and DH seismic tests, as well as from two electrical resistivity traverses, conducted adjacent to three boreholes in which undisturbed soil samples were collected previously to seismic data acquisition. A regression exploratory analysis points out to the advantage of including both N-SPT values as well as depth values in modelling maximum shear modulus, G_0, behaviour.