Risk assessment associated with geotechnical problems Pokhara City, Nepal

• Project/Area Number: 15H02631
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 海外学術
• Research Field: Geotechnical engineering
• Research Institution: The University of Tokyo
• Principal Investigator: Kiyota Takashi 東京大学, 生産技術研究所, 准教授 (70431814)
• Co-Investigator(Kenkyū-buntansha): 桑野 玲子 東京大学, 生産技術研究所, 教授 (80312974)
• Co-Investigator(Renkei-kenkyūsha): IKEDA Takaaki 長岡技術科学大学, 工学研究科, 教授 (40443650) ; KATAGIRI Toshihiko 東京大学, 生産技術研究所, 技術専門職員 (70724459)
• Research Collaborator: YAGIURA Yoshiyuki 基礎地盤コンサルタンツ株式会社
• Project Period (FY): 2015-04-01 – 2018-03-31
• Project Status: Completed (Fiscal Year 2017)
• Budget Amount: ¥39,910,000 (Direct Cost: ¥30,700,000、Indirect Cost: ¥9,210,000); Fiscal Year 2017: ¥10,010,000 (Direct Cost: ¥7,700,000、Indirect Cost: ¥2,310,000); Fiscal Year 2016: ¥8,970,000 (Direct Cost: ¥6,900,000、Indirect Cost: ¥2,070,000); Fiscal Year 2015: ¥20,930,000 (Direct Cost: ¥16,100,000、Indirect Cost: ¥4,830,000)
• Keywords: 地盤陥没 / 表面波探査 / ＵＡＶ / 動的コーン貫入試験 / 液状化 / 現場調査 / 地盤浸食 / UAV / 地中音計測 / 動的貫入試験 / 地盤調査 / 地震 / 豪雨 / 地盤災害 / 陥没

Outline of Final Research Achievements

In order to assess the risk associated with sinkhole problem and earthquake-induced liquefaction in Pokhara, Nepal, a series of field survey, including surface geological reconnaissance, were conducted in Armala area and the city area. A number of sinkholes have been occurring in Armala area since November 2013. Although immediately after the sinkhole event, most of the sinkholes were backfilled by using local sandy and gravelly soils, they were re-activated during the rainy season. The surface geological reconnaissance suggested that the sinkholes are distributed along the old Duhuni Khola or the old Kali Khola. The results also indicate that it would be possible for cavities to be detected by using mini-ram sounding and surface wave test. In the city area, liquefaction assessment was conducted by means of mini-ram sounding. It was found that the city area has a low potential for liquefaction because of soil condition and deep ground water table.

Research Products

• [Int'l Joint Research] Tribhvan University(Nepal)
• [Int'l Joint Research] Tribhvan University(Nepal)
• [Journal Article] FIELD SURVEY ON SINKHOLES IN POKHARA, NEPAL, BASED ON UAV AND SURFACE WAVE TEST (2017)
  • Author(s): 志賀正崇, 清田隆, 桑野玲子
  • Journal Title: SEISAN KENKYU Volume: 69 Issue: 6 Pages: 373-378
  • DOI: 10.11188/seisankenkyu.69.373
  • NAID: 130006230266
  • ISSN: 0037-105X, 1881-2058
  • Open Access
• [Journal Article] The 2015 Gorkha Nepal Earthquake: Insight from Earthquake Damage Survey (2015)
  • Author(s): Goda, K., Kiyota, T., Pokhrel, R.M., Chiaro, G., Katagiri, T., Sharma, K. and Wilkinson, S.
  • Journal Title: Frontiers in Built Environment Volume: 1(8) Pages: 1-15
  • DOI: 10.3389/fbuil.2015.00008
  • Peer Reviewed / Open Access / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Reconnaissance report on geotechnical and structural damage caused by the 2015 Gorkha Earthquake, Nepal (2015)
  • Author(s): Chiaro, G., Kiyota, T., Pokhrel, R. M., Goda, K., Katagiri, T. and Sharma, K.
  • Journal Title: Soils and Foundation Volume: 55(5) Issue: 5 Pages: 1030-1043
  • DOI: 10.1016/j.sandf.2015.09.006
  • Peer Reviewed / Open Access / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Preliminary field assessment of sinkhole damage in Pokhara, Nepal (2015)
  • Author(s): Pokhrel, R. M., Kiyota, T., Kuwano, R., Chiaro, G., Katagiri, T. and Arai, I.
  • Journal Title: International Journal of Geoengineering Case Histories Volume: 3(2) Pages: 113-125
  • Peer Reviewed / Open Access / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Sinkhole damage in Armala area in Pokhara, Nepal: A preliminary survey report (2015)
  • Author(s): Pokhrel, R. M., Kiyota, T., Kuwano, R., Chiaro, G., Katagiri, G. and Arai, I.
  • Journal Title: Bulletin of Earthquake Resistant Structure Volume: 48 Pages: 1-10
  • Open Access / Int'l Joint Research
• [Journal Article] 2015年ネパール地震被害調査報告 (2015)
  • Author(s): 清田隆, 合田且一朗, Rama Mohan POKHREL, Gabriele CHIARO, 片桐俊彦
  • Journal Title: 生産研究 Volume: 67(6) Pages: 91-96
  • NAID: 130005110057
  • Open Access / Int'l Joint Research
• [Presentation] ネパール・ポカラにおける地盤陥没被害の概要と現地調査 (2017)
  • Author(s): 志賀正崇
  • Organizer: 第52回地盤工学研究発表会
• [Presentation] ネパール、ポカラ地域における陥没発生地帯への表面波探査と地下水流音測定の適用 (2016)
  • Author(s): 吉川猛, 清田隆, 桑野玲子, 片桐俊彦, 池田隆明, 柳浦良行, 武政学, R. M. Pokhrel
  • Organizer: 物理探査学会第135回学術講演会
  • Place of Presentation: 室蘭工業大学, 室蘭市
  • Year and Date: 2016-10-26
• [Presentation] Follow-up survey of sinkhole damage in Pokhara, Nepal （Riverbed lowering and subsequent groundwater lowering causing numerous sinkholes since 2013） (2016)
  • Author(s): Yagiura, Y., Takemasa, M., Yoshikawa, T., Kiyota, T., Kuwano, R., Katagiri, T., Ikeda, T. and Pokhrel, R. M.
  • Organizer: International Workshop on Geotechnical Natural Hazards
  • Place of Presentation: Pingtung, Taiwan
  • Year and Date: 2016-09-20
  • Int'l Joint Research
• [Presentation] Investigation into the multiple recent sinkholes in Pokhara, Nepal (2016)
  • Author(s): Kuwano, R., Kiyota, T., Pokhrel, R. M., Katagiri, T., Ikeda, T., Yagiura, Y., Yoshikawa, T. and Kuwano, J.
  • Organizer: the 8th International Conference on Scour and Erosion (ICSE 2016)
  • Place of Presentation: Oxford, the UK
  • Year and Date: 2016-09-12
  • Int'l Joint Research
• [Presentation] Contribution of geostatistical technique to investigate the spatial variation of liquefaction potential in Urayasu City, Japan (2015)
  • Author(s): Pokhrel, R. M., Kiyota, T. and Kajihara, K.
  • Organizer: 6th International Conference on Earthquake Geotechnical Engineering
  • Place of Presentation: クライストチャーチ、ニュージーランド
  • Year and Date: 2015-11-01
  • Int'l Joint Research
• [Presentation] 2015年ネパール・ゴルカ地震による道路における地盤災害調査報告 (2015)
  • Author(s): 清田隆, 池田隆明, 合田且一朗, Pokhrel, R. M., Chiaro, G., 片桐俊彦
  • Organizer: 第35回土木学会地震工学研究発表会
  • Place of Presentation: 東京大学生産技術研究所（東京）
  • Year and Date: 2015-10-06
• [Presentation] ネパール・ポカラで頻発する事前堆積地盤の陥没調査 (2015)
  • Author(s): 新井逸郎, 清田隆, 桑野玲子, Pokhrel, R. M., Chiaro, G., 片桐俊彦
  • Organizer: 第50回地盤工学研究発表会
  • Place of Presentation: 北海道科学大学（札幌）
  • Year and Date: 2015-09-01
• [Presentation] Site investigation of sinkhole damage in the Armala area, Pokhara, Nepal (2015)
  • Author(s): Pokhrel, R.M., Kiyota, T., Kuwano, R., Chiaro, G., Katagiri, T.
  • Organizer: International Conference on Geotechnical Engineering
  • Place of Presentation: コロンボ、スリランカ
  • Year and Date: 2015-08-10
  • Int'l Joint Research
• [Remarks] PhotogrammetryとUAVを用いた地形図作成と地盤災害調査への応用
  • URL: http://www.gdm.iis.u-tokyo.ac.jp/research_field.html
• [Remarks] ネパール・ポカラにおける地盤陥没現象を対象とした様々な原位置調査
  • URL: http://www.gdm.iis.u-tokyo.ac.jp/research_field.html
• [Remarks] ネパール・ポカラで頻発する自然堆積地盤の陥没調査
  • URL: http://www.gdm.iis.u-tokyo.ac.jp/research_field.html