A forensic analysis of the collapse of the
Arecibo radiotelescope in 2021 has concluded that problems in both the
suspension cables and the sockets that held them led to the failures that
precipitated the collapse. The detailed study, by the engineering firm of
Thornton Tomasetti, reported that a combination of five major factors was responsible:
“(1) the manual and inconsistent splay of the wires
during cable socketing, (2) the design of the cable system with relatively low
safety factors, (3) the occurrence of extreme environmental events such as
hurricanes and earthquakes, (4) the non-replacement, repair or bypass of the
sockets where large cable slips were observed, and (5) the addition of
auxiliary cables as isolated cables.”
The Arecibo radiotelescope in better days
(CQ Newsroom archives)
The report concluded that, while further study is needed to determine the service life of cable-socket assemblies, “the risk of socket failure can be mitigated by … (1) controlling the number and geometry of splayed-out wires during cable socketing, (2 and 3) designing cable systems with larger safety factors under gravity and transient loads, (4) monitoring the cable slip and slip rate after cable installation, and (5) designing cable systems with multiple adjacent cables on each span.” (Tnx WP3R)