Recurring Landslides and Debris Flows near Kalli Village in the Lesser Himalayas of Western Nepal

Diwakar, K.C.; Dangi, Harish; Naqvi, Mohammad Wasif; Kadel, Sushma; Hu, Liangbo

doi:10.1007/s10706-023-02450-4

Cited by 4 publications

(6 citation statements)

References 40 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The debris deposition pattern shows that finer particles are deposited very close to the landslide toe and the coarser particles are deposited far away from the landslide area. It is common that large boulders are found to deposit at the bank of the Karnali river, which is around 3 km from the landslide crown area [36]. The total volume of the main debris flow that has already traveled to the Karnali river is more than hundreds of thousands of cubic meters.…”

Section: Landslide and Debris Flows Eventsmentioning

confidence: 99%

Rainfall-Triggered Landslides and Numerical Modeling of Subsequent Debris Flows at Kalli Village of Suntar Formation in the Lesser Himalayas in Nepal

KC,

Naqvi,

Dangi

et al. 2024

Water

Self Cite

View full text Add to dashboard Cite

Hazardous debris flows are common in the tectonically active young Himalayas. The present study is focused on the recurrent, almost seasonal, landslides and debris flows initiated from Kalli village in Achham District of Nepal, located in the Lesser Himalayas. Such geological hazards pose a significant threat to the neighboring communities. The field survey reveals vulnerable engineering geological conditions and adverse environmental factors in the study area. It is found that a typical complete debris transport process may consist of two stages depending on the rainfall intensity. In the first stage, debris flows mobilized from a landslide have low mobility and their runout distance is quite modest; in the second stage, with an increase in water content they are able to travel a longer distance. Numerical simulations based on a multi-phase flow model are conducted to analyze the characteristics of the debris flows in motion, including the debris deposition profiles and runout distances in both stages. Overall, the numerical results are reasonably consistent with relevant field observations. Future debris flows may likely occur again in this area due to the presence of large soil blocks separated by tension cracks, rampant in the field; numerical simulations predict that these potential debris flows may exhibit similar characteristics to past events.

show abstract

Section: Landslide and Debris Flows Eventsmentioning

confidence: 99%

Rainfall-Triggered Landslides and Numerical Modeling of Subsequent Debris Flows at Kalli Village of Suntar Formation in the Lesser Himalayas in Nepal

KC,

Naqvi,

Dangi

et al. 2024

Water

Self Cite

View full text Add to dashboard Cite

show abstract

“…The mass matrix in the explicit time integration algorithm is much simpler to derive than the stiffness matrix in the implicit time integration algorithm, and the mass matrix can be reduced to a diagonal matrix. Compared with the implicit SPFEM proposed by Zhang et al [13], the eSPFEM has two features: (1) it has more concise formulas (no need to form stiffness matrices) and can solve large-scale problems with relatively high stability while taking less time. (2) The eSPFEM is easier to adapt from the existing FEM code; thus, the method can be applied more widely.…”

Section: Theoretical Background Of Spfemmentioning

confidence: 99%

“…The numerical simulation of slope failure using the eSPFEM is divided into two stages: (1) The positions of all the particles are fixed, and gravity is applied to these particles to achieve the initial stress field. (2) The particles are allowed to move, and after the initial shear failure, the unstable soil mass moves and reaches an equilibrium state at a new slope configuration.…”

Section: Cohesive Homogeneous Soil Slopementioning

confidence: 99%

“…Landslides can cause considerable soil loss, thus exerting long-term adverse effects on agricultural production, such as reduced soil productivity, soil water-holding capacity and water quality in streams and rivers [1]. It has been estimated that during severe storm events, which occur once every 20-50 years, steep pasture slopes may experience a loss of up to 10% of their soil area, leading to 36% of personal property being damaged and even casualties [2,3].…”

Section: Introduction 1background Of Landslidesmentioning

confidence: 99%

See 1 more Smart Citation

Slope Stability Analysis Based on the Explicit Smoothed Particle Finite Element Method

Jia,

Jiang,

Huang

et al. 2024

Sustainability

View full text Add to dashboard Cite

A landslide is a common natural disaster that causes environmental damage, casualties and economic losses, which seriously affects the sustainable development of society. In geomechanics, it is one of the largest deformation problems. Herein, the GPU-accelerated explicit smoothed particle finite element method (eSPFEM) for large deformation analysis in geomechanics was developed on the CUDA platform based on high-performance computing using a self-designed eSPFEM program code. The eSPFEM combines the strain smoothing nodal integration techniques found in the particle finite element method (PFEM) framework, which allows for the use of low-order triangular elements without volume locking and avoids frequent information transfer and mapping errors between Gaussian points and particles in PFEM. A numerical simulation of slope instability using the eSPFEM and based on a strength reduction technique was conducted using various examples, including a cohesive homogeneous slope, a non-cohesive homogeneous slope, a non-homogeneous slope and a slope with a thin soft band. The calculation results show that the eSPFEM can be applied to slope stability analysis under different working conditions, simulating the entire process of slope instability initiation, sliding and reaccumulation, and obtaining reliable FOS values. A numerical simulation was conducted to analyse a landslide that occurred in the Zhangjiazhuang tunnel on the Lanzhou–Xinjiang high-speed railway line on 18 January 2016. A natural unsaturated soil slope, a soil slope with a high moisture content and a soil slope with a high moisture content subjected to an earthquake were analysed. The findings of this study are in good agreement with the actual slope failure conditions. The primary triggers identified for the landslide were heavy rainfall and earthquakes. The verification results indicate that the eSPFEM can effectively simulate an actual landslide case, showcasing high accuracy and applicability in simulating the large deformation behaviour of landslides.

show abstract

“…Run-off generated failures generally have low solid concentration, while slope failure or earthquake generated debris flow are typically dominated by the solid proportion. Finally, many past studies [36][37][38][39] have reported the volume of landslide material ranging from hundreds to million cubic meter, it is of interest to examine its impact on the study area. For sensitivity analysis, the basal friction angle is varied from 1 • to 20 • , the solid fraction from 0.25 to 0.85, and the initial debris volume from 4500 to 60,000 m 3 .…”

Section: Sensitivity Analysismentioning

confidence: 99%

Numerical Modelling and Sensitivity Analysis of the Pitztal Valley Debris Flow Event

Naqvi,

Kc,

2023

Geosciences

Self Cite

View full text Add to dashboard Cite

Debris flows characterized by their rapid velocity and composition of water, mud, soil, and boulders, have the potential to inflict significant harm and present hazards to human life, infrastructure, and the natural surroundings. Numerical simulations provide a cost-effective approach for investigating different scenarios, hence boosting comprehension of flow dynamics and interactions. However, accurate modelling of these flows typically face difficult challenges arising from inherent modeling constraints and insufficient historical event data. The primary objective of the present study is to conduct numerical modeling and sensitivity analysis of the debris flow event that occurred in the Pitztal Valley, Austria in August of 2009, based on a multi-phase model for debris flows. The validation of the simulation results involves the comparison with the observed deposition patterns in the field. Various validation factors are employed to evaluate the accuracy of the simulated deposit and demonstrate a satisfactory level of precision in predicting deposition patterns. A sensitivity analysis is also conducted to examine the influence of in situ conditions on the effects of debris flow. The results demonstrate that numerical modelling can play an important role in engineering hazard assessment by analyzing the existing model’s effectiveness in simulating both historical and projected debris flow events.

show abstract

Recurring Landslides and Debris Flows near Kalli Village in the Lesser Himalayas of Western Nepal

Cited by 4 publications

References 40 publications

Rainfall-Triggered Landslides and Numerical Modeling of Subsequent Debris Flows at Kalli Village of Suntar Formation in the Lesser Himalayas in Nepal

Rainfall-Triggered Landslides and Numerical Modeling of Subsequent Debris Flows at Kalli Village of Suntar Formation in the Lesser Himalayas in Nepal

Slope Stability Analysis Based on the Explicit Smoothed Particle Finite Element Method

Numerical Modelling and Sensitivity Analysis of the Pitztal Valley Debris Flow Event

Contact Info

Product

Resources

About