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In modern era, a construction of infrastructure projects necessitates a geotechnical investigation, which usually involves the execution of boreholes and laboratory testing on their samples as well as in-situ testing. A useful test, important for both educational and practical reasons, is the Cone Penetration Test (CPT), used to estimate the strength and compressibility of loose-to-medium dense coarse grained and soft to stiff fine-grained geomaterials, the excavation of which requires special attention. In this paper, a theoretical review on geotechnical surveys, in-situ testing of static cone penetrometer, statistical analysis of results, geotechnical correlations for the evaluation of results along with a dimensioning of the retaining wall with pile boards, is presented. The paper aims at highlighting the use of CPT for selecting the proper type of the temporary retaining structure, necessary to support excavations in loose-soft soils. The case study includes a pump room construction along with its aqueduct, close to Aliakmonas River in Greece. From this point of view, it may offer a rather powerful research design basis than purely experimental methods.

When a construction presents a huge vertical concentrated load (e.g. a bridge) and has to be founded on a ground of insufficient stability, the procedure to be followed is the use of pillars. However, in the case of a seismic event, the pillars are in danger due to: a) their fraction owed to high bending moments, due to the presence of significant horizontal soil movements along their length, b) shear failure of the foundation soil, in the case where the shear stress on a sliding surface, due to the static loading along with the seismic excitation, exceeds the local soil strength, c) a usually upwards pillar shift with respect to its surrounded soil, owed to the liquification of the underground. A description on the methods of analysis corresponding to the dynamic behavior of pillars along with the seismic event, concerning the collapse of the Higashi – Nada bridge of Kobe in Japan – after the earthquake of 17th January 1995 – is then to be presented.