Fibers reinforcement of the fissured clayey soil by desiccation

Grounds and foundations, underground structures

The cracks caused by desiccation induce rapid failures as rapid shallow landslides in stiff and fragile clayey soils. Several environmental structures such as landfill liners and road embankments are often constructed by compaction of a series of soil layers. These works suffered in many cases of disorders due to desiccation. One of the potential valuable techniques to reduce these disorders is the short fibers reinforcement. Fibers reduce the cracks propagation and the geometric cracks characteristics such as the length, depth and opening. The paper presents an experimental characterization of the crack pattern observed in compacted samples at optimum water content (OMC) with and without fibers reinforcement. 2D Image Analysis has been used to investigate the characteristics of the geometric cracks. Alfa natural short fibers used to assure the reinforcement, reduced the carks' propagation by stopping the propagation and reducing their 3D opening (surface opening and depth growth). The role of fibers to improve the tensile strength and reduce the growth of the crack has been well-highlighted. At this stage, a simple model was calibrated to predict the tensile strength for reinforced soil specimens with short fibers considering various fibers contents and fiber's geometrical characteristics.