Effect of rainfalls on slope stability in Manisa region

Rainfall has an important role in triggering slopes all over the world. Rainfall is generally effective in triggering slopes in the north of our country, but when suitable conditions come together, it can also trigger slopes in different regions such as Manisa. Climate change observed in recent years and the resulting changes in rainfall regime and rainfall intensity and duration have increased awareness and interest in slope stability losses as a result of rainfall infiltration. In nature, sloped soils are often semi-saturated. A similar situation applies to the soils in this study. The effects of changes in saturation levels of naturally unsaturated soils on slope slippage safety were investigated in the Manisa - Salihli area. Samples were taken from the soils where slippage was observed due to changes in water content and the properties of the samples were determined in terms of soil mechanics in a laboratory environment. Then, the effects of rainfall intensity and duration on the existing soils for the determined soil properties were investigated with the Itesca-Flac software in two dimensions using the finite difference method. As a result of the study, the mechanical properties of the soils in the Manisa – Salihli region were determined, and the effects of rainfall intensity and duration on the slope stability of the soils under study were examined. As a result of the research, it was concluded that the last 20 years of rainfall averages alone don't have any risk about slope failures, and the numerical analysis results were shared.