Health Assessment of Flood Protecting Haora Earthen Embankment Through Numerical and Field Experiments

Abstract: Health assessments for vital lifeline infrastructures, such as earthen embankments, are crucial as a substantial population resides downstream of these structures. The Hoara River is one such structure that has played a pivotal role in safeguarding the capital city of Tripura, Agartala, in the northeastern state of India for more than six decades. Since its inception, the embankment has witnessed numerous flood events, consistently demonstrating resilience against the natural hazards of flooding. Over time, the embankment has developed particular critical sections or weak zones attributed to erosion, silting, and thriving human settlement along the periphery of the embankment. This situation mandates meticulous and extensive examination to evaluate the safety and stability of the structure. The present study is a humble attempt in this direction. It evaluates the stability of the embankment, with a specific focus on the impact of infiltration forces resulting from rainfall. The assessment employs a comprehensive approach, including on-site visits, field and laboratory examinations of subsoil properties from boreholes, and numerical analyses using the SEEP/W and SLOPE/W modules of GeoStudio (2018). The results of the study offer crucial insights into the embankment's soil characteristics, revealing a cohesive nature followed by layers of medium to stiff clayey silt and substantial fine to medium silty sand. These findings have significant implications for the maintenance and upkeep of the embankment, providing valuable information for understanding its structural behavior and guiding the formulation of suitable preservation strategies.