Thesis
Rainfall-induced landslides in Turkey: an overview and a case study from Rize, NE Turkey
Master of Science (M.S.), Drexel University
Jan 2022
DOI:
https://doi.org/10.17918/00000922
Abstract
This Master of Science thesis presents an overview of the rainfall-induced landslides problem in Turkey. This is a serious and recurring natural hazard that unfortunately results in almost every year in significant economic losses and deaths in Turkey. The thesis presents an overview of the landslide problem in Turkey that includes a summary of relevant information such as the topography, geology, climate, and seismicity of this country. The literature review presents a summary of the most important studies on rainfall-induced landslides in Turkey. The literature review describes the magnitude of this problem and confirms the seriousness of this natural hazard. The rainfall-induced landslide is particularly problematic in the NE region of Turkey. The thesis also involved analyzing a rainfall-induced landslide that occurred in the Rize province, NE Turkey. The rainfall-induced landslides in this region involve shallow failures on unsaturated soils above the natural groundwater table. Using the described unsaturated soil mechanics framework numerical analyses can explain the stable condition before the rainfall event due to the contribution of the apparent cohesion due to soil matric suction. During a rainfall event of sufficient intensity and/or duration, the portion of water that infiltrates into the slope will increase the soil moisture and this, in turn, will result in a decrease of the apparent cohesion that contributes to the pre-storm stability of the slope. The numerical analyses presented predict the level of suction loss overtime during the infiltration process until the slope failure occurs. The methodology used was first validated by analyzing a slope failure in Santa Cruz, California reported by Reid et al. (1988) and analyzed by Collins (1997) and Collins and Znidarcic (2004). Once the numerical methodology was validated it was applied to the failure case history from Rize, NE Turkey. Specifically, the failure was analyzed using the finite element suite of software GeoStudio that includes the programs Seep/W and Slope/W. Seep/W was used to model the rainfall infiltration process, and Slope/W was used to evaluate the stability of the slope. The analyses of the Rize failure used laboratory and field observations reported by Uyeturk (2019). The Rize case history was found to have a pre-storm factor of safety of about 4.9 and a post-storm factor of safety below unity, which is consistent with the observed failure. The thesis hopes to highlight the importance of the recurring natural hazard of rainfall-induced landslides in Turkey, and in particular in the NE region. It also helped identify important gaps and needs of this serious problem in Turkey. For example, need for better monitoring of rainfall events with archiving of data to develop better landslide rainfall thresholds and for analyses likes the ones presented in this thesis. Chapter 7 describes recommendations for future work.
Metrics
1034 File views/ downloads
54 Record Views
Details
- Title
- Rainfall-induced landslides in Turkey
- Creators
- Muhammed Emin Aytekin
- Contributors
- Miguel A. Pando (Advisor)
- Awarding Institution
- Drexel University
- Degree Awarded
- Master of Science (M.S.)
- Publisher
- Drexel University; Philadelphia, Pennsylvania
- Number of pages
- ix, 96 pages
- Resource Type
- Thesis
- Language
- English
- Academic Unit
- Civil/Architectural/Environmental Engineering (1970-2026); College of Engineering (1970-2026); Drexel University
- Other Identifier
- 991016669046704721