Pore size distribution of Brasilia tropical soil in 3 different initial states

Abstract

In the last decades there was an evolution in the analysis of the soil structure, most importantly, there was an improvement in the evaluation and in the ways of determining the mentioned structure and how it relates to the hydro-mechanical behaviour of soils. Due to the necessity of understanding the behaviour of tropical soils under different structures (natural, compacted and slurry) this study was developed by means of the Mercury Intrusion Porosimetry (MIP), enabling the analysis of the structural characteristics of these samples. The main objective of this work is to evaluate how the different structures are affected by external loading and how the changes in the pore sizes influences the hydro-mechanical behaviour of the soil in both, saturated and unsaturated conditions. It has been observed that the results regarding the influence of the structure showed a bimodal behaviour. The structural modification of the soil under study, due to the mechanical and / or hydraulic loading, leads to changes in the structure of the macropores and does not affect the micropores. With this, it is noticed that even fixing the parameters related to the microstructure it is possible to make a good adjustment of the macro. This is justified by the fact that the microstructure of all samples are very similar.