Abstract
Landslides are very common in high altitude regions of the Himalayas. The Chandmari landslide is a recurrent landslide located in the Eastern part of Gangtok, Sikkim—a Northeastern state in India. Intense rainfall in the monsoon is the main triggering factor for landslides in this region. This paper enumerates the contributing parameter for rainfall induced landslides, viz., bedrock hydrogeology and geotechnical properties of soil and studies their impact on the same. A geophysical resistivity survey was carried out to identify the subsurface structure and to get an insight of the water saturation profile below the landslide surface. The result of the resistivity study showed high to moderate conducting zone in the lower elevations of the landslide site. This was contrary to what we measured at the higher elevations, which showed higher resistive zones. This anomaly was profound and revealed the existence of water saturated zones below the surface of landslide at these lower elevations. In addition, resistivity results revealed that the weak water saturated debris layer was parallel to the geological contact that favored movement. Results of geotechnical investigation for soil showed that an average maximum dry density was 1.8 kg/m3 and average optimum moisture content was 31.84%. The results showed that the value of Coefficient of uniformity (Cu) was 6.4 and the value of Coefficient of curvature (Cc) was 0.894. The angle of internal friction and average cohesion values were calculated as 30.57° and 0.2 kPa respectively. A combined hydrological-slope study was performed using SLOPE/W software to understand the relationship of pore water in variations with the aforementioned soil parameters to determine the probability of a landslide occurrence. Finally, the identified conductive feature of the water saturated debris layer was correlated with the calculated slide mass using a slope stability model.
This is a preview of subscription content, log in via an institution.
Buying options
Tax calculation will be finalised at checkout
Purchases are for personal use only
Learn about institutional subscriptionsReferences
Bell FG (2007) Engineering geology, 2nd edn. Butterworth-Heinemann, Oxford, 581 p
Bhasin R, Grimstad E, Larsen JO, Dhawan AK, Singh R, Verma SK, Venkatachalam K (2002) Landslide hazards and mitigation measures at Gangtok, Sikkim Himalaya. Eng Geol 64:351–368
Campbell RH (1975) Soil slips, debris flows, and rainstorms in the Santa Monica Mountains and vicinity, Southern California. US Geol Survey, Prof Pap 851:1–20
Capparelli G, Biondi D, De Luca DL, Versace P (2009) Hydrological and complete models for forecasting landslides triggered by rainfalls. Rainfall induced landslides—Mechanisms monitoring techniques and nowcasting models for early warning systems. In: Proceedings of 1st Italian workshop on landslides, pp 8–10
Chen H, Ito Y, Sawamukai M, Tokunaga T (2015) Flood hazard assessment in the Kujukuri plain of Chiba Prefecture, Japan, based on GIS and multicriteria decision analysis. Nat Hazards 78:105–120
Crosta G (1998) Regionalization of rainfall thresholds: an aid to landslide hazard evaluation. Environ Geol 35:131–145
Dahal RK, Hasegawa S, Yamanaka M, Nishino K (2006) Rainfall triggered flow-like landslides: understanding rom southern hills of Kathmandu, Nepal and northern Shikoku, Japan. In: Proceedings of 10th international congress on IAEG2006, vol 819. The Geological Society of London, pp 1–14
Dubey CS, Chaudhry M, Sharma BK, Pandey C, Singh B (2005) Visualization of 3-D digital elevation model for landslide assessment and prediction in mountainous terrain: a case study of Chandmari Landslide, Sikkim, eastern Himalayas. Geosci J 9(4):363–373
Dutta KK (1966) Landslips in Darjeeling and neighbouring hill-slopes in June, 1950. In: Geological Survey of India, Landslides and Hillside stability in the Eastern Himalayas, vol 15. GSI bulletin series B, Kolkata, 7–30 pp
Igwe O, Effiong BA, Iweanya MR, Andrew OI (2015) Landslide investigation of Ikwette, Obudu Local Government Area of Cross River State, Nigeria. J Appl Geol Geophys 3(3):01–12
Iverson RM (2000) Landslide triggering by rain infiltration. Water Resour Res 36:1897–1910
Ramesh MV, Vasudevan N (2012) The deployment of deep-earth sensor probes for landslide detection. Landslides 9(4):457–474
Singh R, Umrao RK, Singh TN (2014) Stability evaluation of road-cut slopes in the Lesser Himalaya of Uttarakhand, India: conventional and numerical approaches. Bull Eng Geol Environ 73:845–857
Singh TN, Singh R, Singh B, Sharma LK, Singh R, Ansari MK (2016) Investigations and stability analyses of Malin village landslide of Pune district, Maharashtra, India. Nat Hazards 81(3):2019–2030
Acknowledgements
This work is partially funded by Ministry of Earth Sciences, Government of India as part of the research project titled as “Advancing Integrated Wireless Sensor Networks for Real-time Monitoring and Detection of Disasters”. The authors wish to acknowledge the Department of Disaster Management and the Department of Mines & Geology of the government of Sikkim for their unconditional help for carrying out this work. We acknowledge the help and cooperation that we have received from all the team members of Amrita Center for Wireless Networks and Applications. We are gratefully acknowledged the help, guidance and support provided by the Chancellor of Amrita University, Sri. Mata Amritanandamayi Devi.
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2017 Springer International Publishing AG
About this paper
Cite this paper
P, T., Ramesh, M.V. (2017). Slope Stability Investigation of Chandmari in Sikkim, Northeastern India. In: Mikos, M., Tiwari, B., Yin, Y., Sassa, K. (eds) Advancing Culture of Living with Landslides. WLF 2017. Springer, Cham. https://doi.org/10.1007/978-3-319-53498-5_42
Download citation
DOI: https://doi.org/10.1007/978-3-319-53498-5_42
Published:
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-53497-8
Online ISBN: 978-3-319-53498-5
eBook Packages: Earth and Environmental ScienceEarth and Environmental Science (R0)