Comparing Root Cohesion Estimates from Three Models at a Shallow Landslide in the Oregon Coast Range
Abstract
:1. Introduction
- To reexamine previously published root cohesion estimates for the CB1 landslide by Schmidt et al. [25], which was evaluated before the development of breakage models accounting for progressive root failure. Because root cohesion values for the CB1 slide have been cited and used in subsequent studies [19,21,22,26,27], reexamining these values has implications for these existing studies as well as future investigations.
- To compare the results of these three models at an instrumented landslide site where interpretations have implications for other shallow landslides. Because roots in the landslide scarp were surveyed and measured post-failure, data from the CB1 site is uniquely suited to this purpose.
2. Materials and Methods
2.1. Root Breakage Models
2.2. CB1 Landslide Site
2.3. Estimation of Root Thread Strength from Experimental Data
2.4. Root Data from the CB1 Landslide Site
2.5. Application of Root Breakage Models
2.5.1. Wu and Waldron Model (WWM)
2.5.2. Fiber Bundle Model (FBM)
Root Bundle Model-Weibull (RBMw)
2.6. Calculation of Root Cohesion
3. Results
3.1. Scarp-Averaged Cohesion
3.2. Root Cohesion by Depth
3.3. Root Cohesion along the Scarp Perimeter
3.4. Contribution of Cohesion by Species
4. Discussion
5. Conclusions
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
Appendix A
Appendix B
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Model | Maximum Force (kN) | Root Cohesion (kPa) | WWM Reduction Factor |
---|---|---|---|
WWM | 101.2 | 4.6 | 1 |
FBM | 26.1 | 1.2 | 0.26 |
RBMw | 18.3 | 0.8 | 0.18 |
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Cronkite-Ratcliff, C.; Schmidt, K.M.; Wirion, C. Comparing Root Cohesion Estimates from Three Models at a Shallow Landslide in the Oregon Coast Range. GeoHazards 2022, 3, 428-451. https://0-doi-org.brum.beds.ac.uk/10.3390/geohazards3030022
Cronkite-Ratcliff C, Schmidt KM, Wirion C. Comparing Root Cohesion Estimates from Three Models at a Shallow Landslide in the Oregon Coast Range. GeoHazards. 2022; 3(3):428-451. https://0-doi-org.brum.beds.ac.uk/10.3390/geohazards3030022
Chicago/Turabian StyleCronkite-Ratcliff, Collin, Kevin M. Schmidt, and Charlotte Wirion. 2022. "Comparing Root Cohesion Estimates from Three Models at a Shallow Landslide in the Oregon Coast Range" GeoHazards 3, no. 3: 428-451. https://0-doi-org.brum.beds.ac.uk/10.3390/geohazards3030022