Stability Analysis of the Earth Embankments Subjected to Natural Cyclic Processes

Abstract:

The paper brings out the stability analysis of the earth embankments subjected to specific natural cyclic processes such as tides in India and freeze-thaw in Romania. The Sundarban, along the Bay of Bengal, is a low tide-dominated deltaic plain of the Ganga-Brahmaputra-Meghna basin (GBM) spreading over India and Bangladesh around 25,500 sq.km. The 3520km of riverside embankments had been erected to protect the deltaic plain from tidal flooding. The tidal cycle in this region is twice high tide and low tide daily. Presently, the Indian Sundarban Delta is under the threat to embankment failure. The study analyses the stability of an 8 m height embankment in the Gosaba region of Sundarban considering a 2m wide earth filled berm at 6m from the bottom of varying clay core thickness under the transient groundwater flow. Pore pressure, Flow net and Phreatic surface have been obtained by numerical models using FLAC 2D software, thus the factor of safety being analysed. In Romania, built on the of the highway A1 Orăştie-Sibiu section crossing the clayey hills from Aciliu and Apoldu known for their instability, the embankment around the abutment pier from Apoldu broke up at the entry to the Aciliu Viaduct. The layers of permeable soil soaked with water become heavy instead the waterproof layers keep the water above them creating sliding surfaces. The water is channelled to dozens of springs that appear or disappear depending on each micro-slip or fallen water amount. By freezing the water expands on the ground determining additional efforts, the cycle iterating with each rain and freeze-thaw.

• Periodical: Advanced Engineering Forum (Volume 21)
• Pages: 389-396
• DOI: https://doi.org/10.4028/www.scientific.net/AEF.21.389
• Online since: March 2017
• Authors: Smita Tung, Kaustuv Bhattacharya, Gupinath Bhandari, Sibapriya Mukherjee, Ancuţa Rotaru*, Vasile Boboc
• Keywords: Correction Works, Factor of Safety, Flow Net, Freezing-Thaw Process, Landslides, Natural Cyclic Process, Phreatic Surface, Tide

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