Swelling and Compaction Characteristics of Fibre-Reinforced Expansive Soils

The foundations which were placed on problematic soils like expansive soils are causing the swell-shrink behaviour due to moisture changes and the structures built upon these soils are experiencing failures. There are multiple specified foundation approaches to address the swell-shrink issues brought on by these soils. The current study deals with the volumetric changes of natural fine-grained soils having varying liquid limits (WL = 58, 66, 74, and 85%) blended with Recron 3s fibre (0.5, 1, 1.5, 2, 2.5, and 3%). Swelling potential (Sp) is compared with index properties (plasticity index and shrinkage index) with variation in fibre percentage. Swell pressure (Sw) tests were conducted by the constant volume method for the optimum fibre content having different compaction energy levels (IS light and heavy compaction). For soils having a liquid limit range of 58–66%, the Si decreases and then has an increasing tendency. Sw was not affected to a greater magnitude by the inclusion of optimum fibre content, for varying energy levels compacted at OMC and MDD. Irrespective of the energy levels, an increase in the liquid limit of the soils causes an increase in the optimum fibre content (compacted at the maximum magnitude of MDD).