Everyday throughout the world, cranes help move and shape the reality we live in. In turn, these massive machines also require much special attention to ensure balance, and safety to the crew, operator and any other surrounding bodies that could be in the area. If not properly controlled and secured, the equipment can lead to catastrophic events.
In this article. we are going to take a look at some of the worst crane accidents out there. While there are many cases that are due to user error, there are plenty of accidents that could be easily avoided if properly leveling and balancing equipment to ensure the cranes do not tip when lifting the loads. Outrigger pads are essential to this, and can at often times be the determining factor behind safely lifting the heaviest of loads, but sometimes there are instances that we are just never prepared for.
Mecca Crane Collapse - Perhaps known as the most horrific crane collapse in recent times was the Mecca incident of September 11th, 2015. On this fateful day, due to a combination of human error and bad weather, a total of 111 people died, and 394 were injured, from a crawler crane that collapsed over the Masjid al-Haram in Saudi Arabia.
The Masjid al-Haram or The Sacred Mosque and also known as the Great Mosque of Mecca, was under construction for expansion when the disaster struck. The problem was that one of the crawler cranes working on the mosque had not sufficiently secured the boon of the crane and high speed winds caused it to collapse against the eastern roof of the building, trapping people within the debris of the destruction. The accident could of been avoided if properly secured, and after the incident, a report showed that out of the 100 machines that were on site, all of them were reported safely secured with the exception of just that one.
Waikato Crane Accident - In 2010, Auckland, New Zealand, a team was working on building the Huruhuru Cycleway Bridge when destruction struck. A 200 tonne Terex All Terrain crane collapsed due to the embankment which supported the crane, dropping out. The crane was lifting a second beam when each side of the creek fully collapsed. The machine was set up on some "decent" outrigger mats, but as the full weight of the beam came over the outriggers on the bank side of the crane, the temporary embankment simply gave way. It may be possible that heavy rains overnight might have undermined the integrity of the embankment. But also, it is concerning that the news and companies that investigated have only referred to the outrigger pads as "decent," which if safety is primary concern, the outrigger pads should have some more quality than "decent." No one wants just a decent surgeon to perform surgery!
Luckily, no one was severely injured in this incident, but just watching the video, you can imagine how terrifying it would be to witness or experience something like this on the jobsite.
Big Blue - The Big Blue was a Lampson LTL-1500 Transi-Lift heavy lift crawler crane that sadly killed 3 iron workers in the accident. On July 14, 1999, the Big Blue collapsed during the construction of the American Family Field (then Miller Park) baseball stadium in Milwaukee, Wisconsin with a load of over 450 tonnes on the hook. The three iron workers were observing the lift in suspended personnel platform when it was hit by the falling crane. Unfortunately when the crane came down it caught them, and sent them plummeting down in the suspended man-basket, killing them on impact. Five others were injured as 1,200 tons of concrete and debris rained down from above. The crane’s collapse was so powerful that the shockwave was measured on the nearest seismograph, at the University of Wisconsin-Milwaukee.
Upon investigation, it was gathered that the day of the accident, wind speeds were between 20 to 21 miles per hour, with gusts of up to 26 to 27 miles per hour at the time of the collapse, but the boom was only rated at 20 miles per hour. It was later revealed that even though the effects of side winds on the crane itself had been calculated, it had not been considered for the load the crane was lifting. This negligence and failure to recognize the immediate danger was expressed by workers, but the initial company was in such a rush to finish the job it was overlooked, in addition to the sites safety instructor departing from the job three months prior to the incident. The culmination of human error and acts of severe weather were once again the cause of this horrific scene.
New York - Over the years, New York has sadly gone through numerous crane collapses, but the most notorious of them all is the accident of 2008. On March 15th, a luffing-jib tower crane collapsed while trying to anchor to the 18th floor for expansion upwards. Sadly, seven people were killed in this incident in addition to 24 that were injured.
Investigation lead to a couple startling safety concerns and failures. The primary issue was the crew was only using half the recommended polyester strings that were used to support the strings the anchor, which resulted in them snapping due to be overloaded. It was also discovered that the site had already received 13 citations and safety concerns. And even worse, the site was also checked by a New York Department of Business inspector a week prior to the incident. The filed report stated that no safety violations were identified at the site, however, the inspector was later charged with falsifying a report after it was determined that no inspection took place.
Unfortunately, this is far from the only crane collapse to happen in New York, let alone within the last 20 years, there have since been dozens of incidents that have been reported and/or recorded. Even as recently as this last February, there was a reported incident that a crane collapsed at a 31-story building, causing 60 firefighters to respond.
Bellevue, Washington 2006 - On November 16, 2006 at 7:40 PM, a 210 ft. construction crane collapsed killing one person, significantly damaging three buildings, and blocking 108th Avenue NE in downtown Bellevue, Washington. The crane fell landing its middle on the east side of Plaza 305, making the office building partially collapse, also into the north side of the Civica Office Commons without injuring anyone. Unfortunately, the tip of the crane's arm came down onto the Pinnacle Bell Centre Apartments killing a resident on the top-fourth floor and exposing the interior of the second and third. An investigation revealed that cracks at the base of the crane caused by frozen water are likely what caused the accident, but this lead to the creation of a new law that passed specifically aimed at required annual inspections of cranes.
Introduced in 2007 but wasn't in effect till January 1, 2010, the Crane Safety Act requires cranes to be load-tested, inspected, and certified at least annually, after any significant modification or repair of structural parts, and before and after each setup at a new site. Crane owners are required to have an independent professional engineer review and approve plans for any non-standard tower crane base. Crane operators are required to have a valid operators certificate issued by a nationally recognized accrediting agency, have up to 2,000 hours of documented experience, and pass a substance abuse test.
Summary
We looked at some pretty scary and devastating events. While we can always do our best if not better to be safer on the job site and use better equipment such as proper sized outrigger pads, there will sometimes be forces outside of our control. Remember to always be aware of not just your equipment, your surroundings and even as you have learned in this article, the peers around you that help inspect and ensure the safety of the operation. From machine, the weather, load size to height, stabilizers to surrounding area, every part of the process is critical to examine and should not go overseen. Even the smallest detail can lead to large scale destruction or even worse.