Al-Rafidain Engineering Journal (AREJ)

The aim of this research is to analyze the stability of the left shoulder slope of the Derbandikhan Dam failure due to rainfall and earthquake. This slope consists of unsaturated low plasticity clayey soil. All analyses were conducted by using the Geo-Studio program. The field survey was carried out for the study site and the soil samples were taken to perform the necessary laboratory tests to obtain the required soil properties. The field conditions (Rainfall and earthquake) were simulated, where the slope was exposed to rainfall at (24) mm / day intensity to various periods (10, 20, 30, 40, 50 and 60) days. A slope stability analysis was performed at end of each period. Moreover, another analyses were performed by exposed slope to an earthquake at end of each rainfall period.  Safety factor reached to critical value (1) when slope was exposed to the earthquake after (20) days of rain. 

Soil reinforcement is one of the important techniques in geotechnical engineering, which is used to enhanced the engineering properties of soil. Soil reinforcement means, addition of natural or synthetic fibers to soil which act as tension members and sharing together with soil to sustain the applied loads. In soil reinforcement technique different types of fibers having different shapes can be used. The fibers used in soil can be having a shape like staples, chips, yarns, crumbs, bristles/hairs and other shapes. In the present time the using of fibers (especially natural fibers) in the earth construction works represent one of the cost-effective and environmentally friendly ground improvement techniques. The main objective of this paper, is to review the definition, mechanism, and application of using fibers in soil reinforcement through different scientific papers published in this subject. Further, the advantages and executive problems related to using fibers in soil reinforcement were discussed.