### A Numerical Analysis of Landslide Movements Considering the Erosion and Deposition along the Flow Path

https://doi.org/10.22146/jcef.43808

Aminudin Syah(1), Teuku Faisal Fathani(2*), Fikri Faris(3)

(1) Department of Civil Engineering, Faculty of Engineering, University of Lampung, INDONESIA
(2) Department of Civil and Environmental Engineering, Universitas Gadjah Mada, Yogyakarta, INDONESIA Centre for Disaster Mitigation and Technological Innovation (GAMA-InaTEK), Universitas Gadjah Mada, Yogyakarta, INDONESIA
(3) Department of Civil and Environmental Engineering, Universitas Gadjah Mada, Yogyakarta, INDONESIA Centre for Disaster Mitigation and Technological Innovation (GAMA-InaTEK), Universitas Gadjah Mada, Yogyakarta, INDONESIA
(*) Corresponding Author

#### Abstract

Landslides are one of the most frequent disasters which occur widespread in Indonesia. This disaster often causes damages and fatalities. One of the mitigations efforts to reduce potential loss is by predicting the area affected by landslide movement. This research developed a numerical model of landslide movement by incorporating the erosion and deposition laws along the flow path. This model improves the accuracy of the previous models which assume that landslide volume is constant without any consideration for the erosion and deposition. The governing equation of this newly developed model uses the Eulerian numerical approach based on the finite difference scheme. The erosion-deposition laws applied in this research are from Egashira et al. (2001), McDougall and Hungr (2005), and Blanc (2008). The simulation program applies Python programming language and examines an imaginary slope with ellipsoid-shaped of source area. The simulation result shows that the additional erosion-deposition formula can enlarge the volume and the affected area of landslide movement. It is clarified that the erosion rate is a determinant factor affecting the results of calculation.

#### Keywords

Rapid landslide; Erosion law; Finite difference; Entrainment; Landslide travel distance

PDF

#### References

Blanc, T. (2008) Numerical simulation of debris flows with the 2D-SPH depth integrated model. na.

Chen, H., Crosta, G. B. and Lee, C. F. (2006) ‘Erosional effects on runout of fast landslides, debris flows and avalanches: a numerical investigation’, Géotechnique, 56(5), pp. 305–322. doi: 10.1680/geot.2006.56.5.305.

Egashira, S., Ashida, K. and Takahama, J. (1989) ‘Constitutive equation of debris flow’, Ann., D. P. R. I., Kyoto Univ., 32(2), pp. 487–501. Available at: http://ci.nii.ac.jp/naid/10006781514/en/ (Accessed: 28 May 2019).

Egashira, S. (1993) ‘Mechanism of sediment deposition from debris flow (part 1)’, Journal of the Japan of the Society of Erosion Control Engineering, 46(1), p. 186.

Egashira, S. (1997) ‘Constitutive equations of debris flow and their applicability’, in Proc. 1st Int. Conf. on Debris-Flow Hazards Mitigation, 1997, pp. 340–349.

Egashira, S., Itoh, T. and Takeuchi, H. (2001) ‘Transition mechanism of debris flows over rigid bed to over erodible bed’, Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere. Elsevier, 26(2), pp. 169–174.

Egashira, S., Miyamoto, K. and Ito, T. (1997) ‘Bed-load rate in view of two phase flow dynamics’, Proceedings of Hydraulic Engineering. Japan Society of Civil Engineers, 41, pp. 789–794.

Fathani, T. F., Legono, D. and Alfath, M. A. (2017) ‘Sensitivity Analysis of Depth-Integrated Numerical Models for Estimating Landslide Movement’, Journal of Disaster Research. Fuji Technology Press Ltd., 12(3), pp. 607–616.

Fathani, T. F., Legono, D. and Karnawati, D. (2017) ‘A numerical model for the analysis of rapid landslide motion’, Geotechnical and Geological Engineering. Springer, 35(5), pp. 2253–2268.

Hungr, O. (1995) ‘A model for the runout analysis of rapid flow slides, debris flows, and avalanches’, Canadian Geotechnical Journal. NRC Research Press, 32(4), pp. 610–623.

Hungr, O. (2007) ‘Dynamics of rapid landslides’, in Progress in landslide science. Springer, pp. 47–57.

Hungr, O. and Evans, S. G. (2004) ‘Entrainment of debris in rock avalanches: An analysis of a long run-out mechanism’, GSA Bulletin, 116(9–10), pp. 1240–1252. doi: 10.1130/B25362.1.

McDougall, S. and Hungr, O. (2004) ‘A model for the analysis of rapid landslide motion across three-dimensional terrain’, Canadian Geotechnical Journal. NRC Research Press, 41(6), pp. 1084–1097.

McDougall, S. and Hungr, O. (2005) ‘Dynamic modelling of entrainment in rapid landslides’, Canadian Geotechnical Journal. NRC Research Press, 42(5), pp. 1437–1448.

Miyamoto, K. (2010) ‘Numerical simulation of landslide movement and Unzen-Mayuyama disaster in 1792, Japan’, Journal of Disaster Research. Fuji Technology Press, 5(3), pp. 280–287.

Pastor, M. et al. (2014) ‘Application of a SPH depth-integrated model to landslide run-out analysis’, Landslides. Springer, 11(5), pp. 793–812.

Pirulli, M. and Pastor, M. (2012) ‘Numerical study on the entrainment of bed material into rapid landslides’, Geotechnique. Thomas Telford, Ltd., Thomas Telford House London E 14 4 JD United Kingdom, 62(11), pp. 959–972.

DOI: https://doi.org/10.22146/jcef.43808

#### Article Metrics

Abstract views : 2833 | views : 2480

### Refbacks

• There are currently no refbacks.