Geotechnical and
Geological Investigation of Critical Slopes along Balipara-Charduar-Tawang Road
in Vartak area, Arunachal Pradesh, India
Singh Deepak Kumar, Verma Amit Kumar and Singh T.N.
Disaster Advances; Vol. 19(1); 7-16;
doi: https://doi.org/10.25303/191da07016; (2026)
Abstract
Landslides are a significant concern in the Himalayan region of India, particularly
affecting large areas along the Balipara-Chardwar-Tawang (BCT) road. This study
presents a comprehensive study involving field and laboratory investigations for
slope stability analysis for two critical slopes between the Tippi and Sessa villages.
Field investigations, such as electrical resistivity and standard penetration tests,
were conducted while laboratory experiments were conducted to determine the engineering
properties of soil and rocks following standard codes. Geological mapping of these
two BCT road slopes revealed steep slopes ranging from 35° to 60°. The strata primarily
consist of silty sand overlying bedrock, with the rock's uniaxial compressive strength
(UCS) value of more than 20.0 MPa.
Slope stability analysis indicated that both slopes are vulnerable to landslides,
with the factor of safety less than the required thresholds for both static and
seismic conditions. Detailed mitigation measures are proposed, including the design
of soil nails and anchors. Numerical analysis post-installation of these mitigation
measures shows an improvement in the factor of safety, surpassing the recommended
value of 1.05 for seismic and 1.30 for static conditions.
