Talukdar, Priyanka
Influence of drainage blanket on the sustenance of an earthen dam with a cracked central core - Vol.103(1),Mar - USA Springer 2022 - 215-226p.
The occurrence of cracks in earthen dams, due to hydraulic fracturing or differential settlement, can have serious consequences and might even lead to its collapse. Soil filters and drainage blankets are necessarily provided in earthen dams for safeguarding the stability of the dam against seepage-induced flow through the dam body. Generally, in a zoned earthen dam, the drainage blanket is applied between the impervious central core and the downstream shell. This study reports the benevolent role of a drainage blanket in case there is an incidental cracking in the core of a zoned earthen dam. As both horizontal toe and inclined chimney blankets are used in earthen dams; the study encompasses both the types of drainage blankets. Finite element-based ‘Coupled Stress/PWP’ analysis is implemented to find out the response of the dam with and without the drainage blankets. The phreatic surface, seepage velocities and hydraulic gradients are monitored for different cases. It is concluded that the presence of drainage blankets do not necessarily reduce the possibility of core cracking through hydraulic fracturing. However, it necessarily controls the movement of water inside the dam body if the core has incidentally cracked, and continues to channelize the water toward the exit drain of the dam toward the heel of downstream face, thereby maintaining its long-term performance until proper rectification measures are not adopted.
Humanities and Applied Sciences
Influence of drainage blanket on the sustenance of an earthen dam with a cracked central core - Vol.103(1),Mar - USA Springer 2022 - 215-226p.
The occurrence of cracks in earthen dams, due to hydraulic fracturing or differential settlement, can have serious consequences and might even lead to its collapse. Soil filters and drainage blankets are necessarily provided in earthen dams for safeguarding the stability of the dam against seepage-induced flow through the dam body. Generally, in a zoned earthen dam, the drainage blanket is applied between the impervious central core and the downstream shell. This study reports the benevolent role of a drainage blanket in case there is an incidental cracking in the core of a zoned earthen dam. As both horizontal toe and inclined chimney blankets are used in earthen dams; the study encompasses both the types of drainage blankets. Finite element-based ‘Coupled Stress/PWP’ analysis is implemented to find out the response of the dam with and without the drainage blankets. The phreatic surface, seepage velocities and hydraulic gradients are monitored for different cases. It is concluded that the presence of drainage blankets do not necessarily reduce the possibility of core cracking through hydraulic fracturing. However, it necessarily controls the movement of water inside the dam body if the core has incidentally cracked, and continues to channelize the water toward the exit drain of the dam toward the heel of downstream face, thereby maintaining its long-term performance until proper rectification measures are not adopted.
Humanities and Applied Sciences