A soil mechanics approach to study soil compaction and consolidation

Abstract

One major limitation to sustainable soil management in agricultural and forest operations has been related to the strength of the soil. Soil strength varies depending on its pedology or due human activities on the soil, which may cause soil compaction. Soil compaction can occur due to the fact that at the moment of accomplishment of the mechanized operations, there are no controls of the soil moisture or of the soil load support capacity. Thus, it becomes important to determine the soil moisture at which the soil can be submitted to the mechanized operations, as well as, to quantify the damages caused to soil structure, when the applied pressures exceeds the soil load support capacity. This paper presents an application of the Bearing Capacity Model which is the adjustment of the precompression stress ( p) as a function of gravimetric (U) or volumetric water content (θ) or matric suction (ψm), to study soil compaction and consolidation and the use of the standard Proctor test for agriculture propose. The results of this study indicate that the use of the Bearing Capacity Model, and the precompression stress determined after the traffic, allowed to quantify the compressive behavior of the soil and the effects of the mechanized operations on the soil structure. Therefore, it is believed that the precompression stress may be used as an auxiliary criterion in planning the mechanized operations in order to avoid soil structure degradation. Although some researchers are using the standard Proctor test for agricultural purposes, it does seem better suited for these studies due to the fact that to do this test the soil structure is destroyed.