CPT—DMT Correlations on Regional Soils from Croatia

Abstract

This paper was prepared based on in situ measurements carried out by the authors using the CPTu and DMT static penetration probes. The list of study sites includes seven specific locations in the northern parts of Croatia and one study site on the southern border of the country. The sites were selected based on the criterion of soil type, which falls into the category of soft to firm, slightly over-consolidated silty clays and silty sands. Intermediate soils are prevalent in the wider region, and most engineers deal with them in their everyday practice. For this reason, local characterization is of most importance for engineering purposes. In this investigation, results of in-situ tests are compared in order to validate the quality of the constrained modulus obtained from a CPT test to the one obtained by a DMT flat dilatometer. A comparison was made between the CPT test cone resistance and two DMT parameters—normalized modulus and horizontal stress index . Dependencies were analyzed for the main soil groups and intermediate data groups. Clay soils were divided into two subgroups based on the identification parameter , while silty soils were analyzed in three subgroups. The results for each subgroup differed significantly, and the analyses showed deviations from published values, especially for the intermediate soil groups. The usefulness of the application is demonstrated with examples at two sites, showing improvements over the most commonly used formula for the constrained modulus from the CPT test.

Comparison of the Piezocone Penetrometer (CPTU) and Flat Dilatometer (DMT) Methods for Landslide Characterisation

“…The locations of the landslide at the cemetery in Bedekovčina (Krapinsko-zagorska County) and the landslide in Kravarsko (Zagrebačka County) are shown in Figure 1. In both locations, the soil is extremely heterogeneous, and the in situ probes are used for detecting problematic layers prone to sliding [16]. This research also shows that in addition to lithological and geological investigations, it is very important to put comprehensive research into the context of hydrogeological conditions because they are the most common trigger for the initiation of the sliding process.…”

Design of Cone Penetration Test Data Relay Transmission by Magnetic Communication

“…Cone penetration test (CPT) refers to a process that drives the probe with sensors into the soil through moderate and stable pressure at a constant speed as far as possible and measures the stress from the probe tip and the friction from the side wall in this process. After analyzing the stress from the probe at different depths by means of statistics, we can infer the properties of a soil layer [1][2][3]. CPT is characterized by a lower cost but higher reliability.…”