Relazione tra la conducibilità termica e le caratteristiche fisiche meccaniche delle terre.

The thermal conductivity is applied in several sectors where the most common is the low enthalpy geothermal. In the recent years, it is recorded an increasing in the application of thermal pumps. In this sector, the thermal conductivity has a primary role because it is a fundamental parameter in the beginning phase of the installation of the pump. Between the new sectors, there are the study of the thermal field around the buried cables and the analysis of the behavior of the soil after the application of specific methods of cultivation. The aim of this project is that to applied the knowledge of the thermal conductivity as in the acquisition phase as in the processing phase. The research is founded on the previous experience of Alfia Pasquini. Her job is reassumed in the work: “La conducibilità termica delle rocce e dei terreni: perfezionamento di misure in laboratorio finalizzate alla valutazione delle potenzialità dei sistemi di geoscambio” of the 2010. The purpose of the project is also increasing the data acquired in temperate climates. indeed, the most data are acquired at cold climes. The instrument applied to carry out the measures is a A5000T thermal probe. The following job provides for an experimentation phase and, after the definition of the guide lines how to acquire the data, the methodology is applied on 24 samples; 12 sands and 12 silt/clay. The thermal conductivity of the samples is correlated with other parameters of the soils, this is done by the application of the cluster analysis and by verifying the results and the obtained clusters. The theorical principles of the three macro-themes on which is founded the thesis are been expressed in the first chapters. The principal themes are: the thermal conductivity, the geotechnics and the cluster analysis. The basic theory is expressed to understand the operation and the choices taken subsequently. The thermal conductivity principles are described as mathematical formulas taking in consideration the application sector, the geology and the materials examined, the soils. After the studying of the factors that influenced the thermal conductivity and the principal sectors where are conducted the thermal conductivity studies. Then, the correlations between the thermal conductivity and the soils parameters are verified. Between the indexes of soils are evaluated some that, by bibliography studying, are directly correlated with the conductivity like the porosity and the humidity. Of the others parameters considered, the correlation with the thermal conductivity is not known, for example the plasticity index and the shale activity index.