IBIS-FM radar as a tool for monitoring hill slopes during excavations in hydropower projects: A case study from Bhutan Himalayas
Excavation is common in the construction of hydropower projects. Monitoring for both stable and unstable slopes is a pressing requirement during progressive excavations with or without cut-slope support measures. The present study is about an excavation carried out in a proposed concrete gravity dam...
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KeAi Communications Co., Ltd.
2022-04-01
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| Series: | Energy Geoscience |
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S2666759221000603 |
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| author | K.R. Praveen Jamyang Chophel Jigme Wangchuk Karma Tshewang Naveen Chander Bansal |
| author_facet | K.R. Praveen Jamyang Chophel Jigme Wangchuk Karma Tshewang Naveen Chander Bansal |
| author_sort | K.R. Praveen |
| collection | DOAJ |
| description | Excavation is common in the construction of hydropower projects. Monitoring for both stable and unstable slopes is a pressing requirement during progressive excavations with or without cut-slope support measures. The present study is about an excavation carried out in a proposed concrete gravity dam site on the right bank slope of the Punatsangchhu River in western Bhutan. During the excavation, the right bank abutment witnessed multiple events of slope failures of various magnitudes. One major landslide occurred on 23 July 2013 in the toe of the right abutment, where foliation/multiple sheared/fractured zones/seams in quartz-feldspathic biotite gneiss dip towards the valley. During further excavations/piling works, a subsequent landslide on the downstream, within the body of the July 2013 landslide, occurred on 12 August 2016. As a result, a real-time monitoring of the slope became necessary to facilitate further excavations for achieving the dam foundation. Thus, the advanced slope monitoring instrument like Image By Interferometric Survey – Frequency Modulated (IBIS-FM) radar was deployed for monitoring the right bank slope during the excavation for the construction of ∼129 m high dam. The displacement of the hill slope is assessed based on this system by monitoring point locations as well as areas by assigning different threshold values for providing timely alerts. This real-time monitoring was effective in identifying the reactivation of August 2016 landslide that occurred on 22 January 2019. Thus, this study showcases the efficiency of IBIS-FM radar in monitoring slope instability with sub-millimeter accuracy on a near real-time basis. |
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| format | Article |
| id | doaj.art-9abaeb3f22644f279ff126c18fec2a42 |
| institution | Directory Open Access Journal |
| issn | 2666-7592 |
| language | English |
| last_indexed | 2024-12-13T15:20:21Z |
| publishDate | 2022-04-01 |
| publisher | KeAi Communications Co., Ltd. |
| record_format | Article |
| series | Energy Geoscience |
| spelling | doaj.art-9abaeb3f22644f279ff126c18fec2a422022-12-21T23:40:35ZengKeAi Communications Co., Ltd.Energy Geoscience2666-75922022-04-0132211217IBIS-FM radar as a tool for monitoring hill slopes during excavations in hydropower projects: A case study from Bhutan HimalayasK.R. Praveen0Jamyang Chophel1Jigme Wangchuk2Karma Tshewang3Naveen Chander Bansal4Corresponding author.; Punatsangchhu-I Hydroelectric Project, Wangdue Phodrang, BhutanPunatsangchhu-I Hydroelectric Project, Wangdue Phodrang, BhutanPunatsangchhu-I Hydroelectric Project, Wangdue Phodrang, BhutanPunatsangchhu-I Hydroelectric Project, Wangdue Phodrang, BhutanPunatsangchhu-I Hydroelectric Project, Wangdue Phodrang, BhutanExcavation is common in the construction of hydropower projects. Monitoring for both stable and unstable slopes is a pressing requirement during progressive excavations with or without cut-slope support measures. The present study is about an excavation carried out in a proposed concrete gravity dam site on the right bank slope of the Punatsangchhu River in western Bhutan. During the excavation, the right bank abutment witnessed multiple events of slope failures of various magnitudes. One major landslide occurred on 23 July 2013 in the toe of the right abutment, where foliation/multiple sheared/fractured zones/seams in quartz-feldspathic biotite gneiss dip towards the valley. During further excavations/piling works, a subsequent landslide on the downstream, within the body of the July 2013 landslide, occurred on 12 August 2016. As a result, a real-time monitoring of the slope became necessary to facilitate further excavations for achieving the dam foundation. Thus, the advanced slope monitoring instrument like Image By Interferometric Survey – Frequency Modulated (IBIS-FM) radar was deployed for monitoring the right bank slope during the excavation for the construction of ∼129 m high dam. The displacement of the hill slope is assessed based on this system by monitoring point locations as well as areas by assigning different threshold values for providing timely alerts. This real-time monitoring was effective in identifying the reactivation of August 2016 landslide that occurred on 22 January 2019. Thus, this study showcases the efficiency of IBIS-FM radar in monitoring slope instability with sub-millimeter accuracy on a near real-time basis.http://www.sciencedirect.com/science/article/pii/S2666759221000603IBIS-FM radarGB-InSARExcavationsReal-time monitoringSlope instabilityLandslide |
| spellingShingle | K.R. Praveen Jamyang Chophel Jigme Wangchuk Karma Tshewang Naveen Chander Bansal IBIS-FM radar as a tool for monitoring hill slopes during excavations in hydropower projects: A case study from Bhutan Himalayas Energy Geoscience IBIS-FM radar GB-InSAR Excavations Real-time monitoring Slope instability Landslide |
| title | IBIS-FM radar as a tool for monitoring hill slopes during excavations in hydropower projects: A case study from Bhutan Himalayas |
| title_full | IBIS-FM radar as a tool for monitoring hill slopes during excavations in hydropower projects: A case study from Bhutan Himalayas |
| title_fullStr | IBIS-FM radar as a tool for monitoring hill slopes during excavations in hydropower projects: A case study from Bhutan Himalayas |
| title_full_unstemmed | IBIS-FM radar as a tool for monitoring hill slopes during excavations in hydropower projects: A case study from Bhutan Himalayas |
| title_short | IBIS-FM radar as a tool for monitoring hill slopes during excavations in hydropower projects: A case study from Bhutan Himalayas |
| title_sort | ibis fm radar as a tool for monitoring hill slopes during excavations in hydropower projects a case study from bhutan himalayas |
| topic | IBIS-FM radar GB-InSAR Excavations Real-time monitoring Slope instability Landslide |
| url | http://www.sciencedirect.com/science/article/pii/S2666759221000603 |
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