Statistical comparison between the adjustment equations of the water retention curve in sanitary landfills coverage soil

Residual soils result from chemical weathering, so their characteristics depend on environmental factors, in addition to origin, topography, drainage and geological age. In the unsaturated condition, the behavior of soils is conditioned by suction, which refers to the state of the soil under reduced pressure. The aim of this study is to compare the water retention curve fitting equations in the study of tropical unsaturated soils through the filter paper technique and the analytical analysis of the data obtained in this test. By performing the analysis of the statistical evaluation parameters used in this study and the proximity of its values to the necessary boundary conditions defined for the equation to explain the soil suctioning behavior of the soil as it loses moisture naturally to the environment, it was verified that the Van Genuchten equation appeared to be the most suitable.