The increasing demand to reuse excavation materials, to use soil in place or materials with high fine contents in the construction of Mechanically Stabilized Earth (MSE) structures leads to the extensive application of soil stabilization technics such as lime, cement or fly ash treatment. Soil treatment is an economical solution to exploit poor in-situ materials that cannot be implemented in their natural state. In other words, the treatment improves the physical parameters of the soils improving its workability. However, such treatments also alter the chemical parameters of soil such as alkalinity in a durable manner. The pH will remain well above 10 for an extended period even at low rates of application. For MSE structures reinforced with PET based geosynthetic uses. It is well established that PET is only suited for soil having pH ranging from 4 to 9. In highly alkaline environment, the degradation mechanism is strongly accelerated particularly when mechanical stresses are applied on the material. Therefore, the use of PET in treated backfill is a clear risk for a structure integrity. This paper will propose an extensive review treatment technics detailing the evolution of the soil alkalinity with time, then we will provide technical data showing the performances of PET reinforcement materials when exposed to alkalinity in the conditions of reinforcement applications, finally we will propose alternative solution such as the use of PVA reinforcement material and present their performances.
Menu