The suspended platform of the Arecibo Observatory collapsed on December 1, 2020, after 57 years of illustrious service to the scientific community. This article reflects on the collapse from a structural engineering perspective. It explores issues that most likely contributed, including the cable terminations and their performance under loading, corrosion, fatigue, safety factors, the dynamic demands on the remaining cables when one of them suddenly snaps, and the dynamics of the suspended platform during its pendular swing. The article is based on publicly available reports from the news media, photographs, and published video recordings of the collapse sequence. These were expanded with relevant studies collected from the literature and with publicly available technical reports from structural engineering consultants that evaluated the structure during its final months. It is organized as a sequence of events, starting with the first cable failure on August 10, 2020, the second failure on November 6, 2020, and the final collapse. Despite the limitations, it is concluded that corrosion does not seem to have played a significant role, and that the failure of the first cable was most likely due to flaws during the fabrication of the cable/socket connection. These will be reviewed and updated once the forensic analyses of the failed elements are concluded and made public.
Abstract The suspended platform of the Arecibo Observatory collapsed on December 1, 2020, after 57 years of illustrious service to the scientific community. This article reflects on [...]