{"id":41792,"date":"2022-09-29T06:43:55","date_gmt":"2022-09-29T06:43:55","guid":{"rendered":"https:\/\/blogs.agu.org\/landslideblog\/?p=41792"},"modified":"2022-09-29T06:43:55","modified_gmt":"2022-09-29T06:43:55","slug":"bijie-city-1","status":"publish","type":"post","link":"https:\/\/blogs.agu.org\/landslideblog\/2022\/09\/29\/bijie-city-1\/","title":{"rendered":"The causes of the 3 January 2022 landslide at Bijie City in Guizhou Province, China"},"content":{"rendered":"

The causes of the 3 January 2022 landslide at Bijie City in Guizhou Province, China<\/h4>\n

On 3 January 2022 a major landslide occurred in the Jinhaihu District of Bijie City in Guizhou Province, China.\u00a0 The landslide, which occurred at a construction site, killed 14 people, whilst a further three people were injured.\u00a0 The causes of this landslide have been reviewed in a paper (Tao et al.<\/em> 2022<\/a>) published in the journal Landslides<\/em><\/a>.<\/p>\n

The location of the landslide is 27.233, 105.463. The site, which was excavated to allow construction of a training facility for Bijie First People\u2019s Hospital, consisted of a slope that was cut to create three benches.\u00a0 The image below, from the paper, provides a drone overview of the aftermath of the landslide:-<\/p>\n

\"The

The aftermath of the landslide 3 January 2022 landslide at Bijie in China. Image from Tao et al.<\/em> (2022)<\/a>.<\/p><\/div>\n

.<\/p>\n

The topography of the slope was not steep – just 15 degrees.\u00a0 On the day of the landslide, 18 mm of rainfall fell, although there had been some snowfall and melt in late December that may have contributed to the groundwater level.\u00a0 It appears that it was high pore water pressures that triggered the failure.<\/p>\n

The underlying cause of the landslide was the geological setting.\u00a0 The site was a dip slope<\/a>, in which there was a weak geological layer orientated sub-parallel (at 13 degrees) to the topographic slope.\u00a0 The strata consisted of intensely weathered mudstones sitting over weak sandstones.\u00a0 Excavation of the slope exposed a thin (3 cm), particularly weak layer in the underlying sandstones,\u00a0 creating a free face that allowed sliding. Joints towards the crown of the slope provided further weakness and allowed infiltration of water.<\/p>\n

The slope has undergone a smaller failure in October 2021, but construction continued.\u00a0 The landslide of 3 January 2022 had a volume of 35,000 cubic metres, a length of 77 m and a thickness of up to 8 m.\u00a0 The debris moved about 30 m.\u00a0 Failure occurred over about 15 seconds.<\/p>\n

Tao et al.<\/em> (2022)<\/a> appear to have been careful not to ascribe blame for the landslide, but the event asks some interesting questions for me:<\/p>\n

    \n
  1. Did the ground investigation identify the existence of the dip slope condition and the presence of the weak interlayer?<\/li>\n
  2. Did the design recognise the potential for failure, and if so how was this to be managed?<\/li>\n
  3. Given the 20,000 cubic metre failure in October 2021, was there a reconsideration of the geological setting of the site, and was the design or construction plan changed?<\/li>\n
  4. Was there monitoring at the site?\u00a0 If not, why not? Were there any signs of the development of instability prior to the failure?<\/li>\n<\/ol>\n

    This is a really interesting example of a failure triggered during construction.\u00a0 One aim of site investigation and detailed design is to avoid the devastating consequences of a failure of this type.\u00a0 The landslide at Bijie city is a great case study that illustrate what happens when this does not go to plan.<\/p>\n

    .<\/p>\n

    Reference<\/h4>\n

    Tao, T., Shi, W., Liang, F.\u00a0et al.<\/i> 2022. Failure mechanism and evolution of the Jinhaihu landslide in Bijie City, China, on January 3, 2022.<\/a> Landslides<\/i>. https:\/\/doi.org\/10.1007\/s10346-022-01957-w<\/p>\n

     <\/p>\n","protected":false},"excerpt":{"rendered":"

    A new paper in the journal Landslides (Tao et al. 2022) describes the very interesting causes of the 3 January 2022 landslide at a construction site at Bijie City in Guizhou Province, China, which killed 14 people.<\/p>\n","protected":false},"author":22,"featured_media":41795,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[544],"tags":[16,30709,881,469,959,17,788],"class_list":["post-41792","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-review-of-a-paper","tag-china","tag-dip-slope","tag-east-asia","tag-featured","tag-landslide-report","tag-research","tag-review-of-a-paper-2"],"_links":{"self":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/41792","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/users\/22"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/comments?post=41792"}],"version-history":[{"count":0,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/41792\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media\/41795"}],"wp:attachment":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media?parent=41792"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/categories?post=41792"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/tags?post=41792"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}