미 연방교통안전위원회(NTSB), 미 플로리다 보도교 붕괴 사고 새 보고서 발표 NTSB Provides Update to Report on Collapsed Florida Pedestrian Bridge

NTSB Provides Update to Report on Collapsed Florida Pedestrian Bridge

August 23, 2018 Shane Hedmond

On March 15, 2018, 6 people were killed and 8 others were injured when an under construction pedestrian bridge collapsed in Florida.  Several months later, the National Transportation Safety Board (NTSB) released their preliminary report while conducting an official investigation. The NTSB has recently released an “Investigative Update” to their preliminary report.

NTSB

Full Report: INVESTIGATIVE UPDATE: Collapse of Pedestrian Bridge Under Construction Miami, Florida (HWY18MH009) | NTSB

* NTSB [National Transportation Safety Board] 

미 연방교통안전위원회

미 연방교통안전위원회(NTSB), 미 플로리다 보도교 붕괴 사고 새 보고서 발표 2018년 3월 15일 플로리다에서 공사 중인 보행교량이 붕괴되면서 6명이 숨지고 8명이 다쳤다.  NTSB는 최근 예비 보고서에 대한 "조사 업데이트 버전"을 발표했다. 예비 보고서가 5월에 발표된 이후, NTSB는 가장 최근의 보고서에서 강조된 많은 추가 조사를 수행했다. 이 조사 결과는 "감압 막대기, 포스트 텐션 잭" 그리고 고장점 주위에서 모두 분석되었다.. NTSB가 예정한 대다수의 사람들과 기업들과도 인터뷰가 이루어졌지만, 나머지는 이번 달에 완료될 예정이라는 점에 주목했다. Related Article 미 플로리다 보도교 붕괴로 최소 4명 사망 10명 부상  VIDEO: At least 4 killed after pedestrian bridge collapses in Florida http://conpaper.tistory.com/64551 황기철 콘페이퍼 에디터 큐레이터 Ki Cheol Hwang, conpaper editor, curator

Since the preliminary report was released in May, the NTSB has conducted many additional tests, which are highlighted in the most recent report.  The post-tensioning rods, post-tensioning jacks, and concrete around the failure points have all been analyzed and the report states that there weren’t any “notable material issues,” found up to this point.

       

Interviews have also been conducted with the majority of people and businesses the agency plans to talk to, but they did note that the remaining interviews are scheduled to be completed this month.

 

  NTSB description: Location: Bottom of diagonal member 11 east face, looking to the west. Time stamp: March 13, 2018, 

  at 1:29:15 p.m., labels added by the NTSB. (Source: Munilla Construction Management)

Perhaps the most significant information that was released in the report were pictures showing cracking around diagonal member 11.  Vertical member 11 was in process of being re-tensioned when the collapse occurred. The bridges diagonal members were de-tensioned, per the plans, on March 10, 5 days prior to the collapse.

The preliminary report included several pictures, which were dated in February, of very small cracks near diagonal member 11.  The pictures released in the latest report, dated March 13 (2 days before the collapse), show much more substantial cracking.

The NTSB’s investigation is still under way and the group has not yet determined the probably cause of the incident.

kcontents