Analysis of Dispersivity in Marine Clays of Cartagena de Indias, Colombia

Abstract

This study assessed the dispersivity of soils extracted from the northern region of Cartagena de Indias (Colombia) using the pinhole test, crumb test, and chemical–microstructural analyses. Dispersive soils are susceptible to erosive phenomena upon contact with water, yet they have not been adequately characterized in the city. To evaluate the dispersivity degree of different deformed and undisturbed soil samples, soil characterization tests included particle size analysis, chemical composition, Atterberg limits, specific gravity, and compaction. The results showed that the soils are highly plastic clays (i.e., CH) with a slight to moderate dispersivity level (i.e., ND3) according to the pinhole test and a moderate degree of dispersivity confirmed by the crumb test. The extracted soil sample sodium levels ranged from 0.72% to 1.94%, and the soil had an optimal moisture content of 26% and a maximum apparent dry unit weight of 13.87 kN/m3. According to standards and results, Cartagena de Indias’s studied marine clays are unsuitable for civil construction due to the degree of uncertainty in their behavior.

Keywords

• marine clays
• dispersivity
• pinhole test
• crumb test