HALIFAX – A provincial government study found that the collapse of a 68-tonne construction crane in Halifax during post-tropical Storm Dorian was the result of a weld failure in the lower parts of the tower.
No one was killed or injured when the crane fell during the September 7, 2019 storm.
An engineering report included in the document released today concludes that the bend occurred in gusts of wind up to 107 kilometers per hour, even though the tower was designed for wind speeds of up to 160 km / h.
BMR Structural Engineering determined that the fault occurred in a section of the mast between six and nine meters above the base where a weld failed and a diagonal member of the mast was separated from a vertical member.
According to the report, an analysis of the metal revealed corrosion, pores and cracks and “other weld defects in welded joints”.
However, BMR determined that the crane was properly prepared for the storm and that it was placed in what is known as the “weather vane mode”, in which the crane’s brakes are released and it is allowed to turn with the wind direction in a storm.
The report also states that the crane was inspected as needed before it collapsed.
Overall, the investigation found that the owner and operator of a tower crane meets the safety standards of the province and Canada as well as all legal and regulatory requirements of the province.
“The investigation found that the weld failure caused the diagonal tube to detach from the vertical member of the mast and transfer the weight carried by the four vertical posts of the mast to only three of its posts, causing the tower section to rotate and fail,” it said it concluded in the report.
The Department of Labor announced in a press release that it will meet with all tower crane owners and operators in the province to review the results of the investigation.
Operators must ensure that all crane masts are “thoroughly cleaned, inspected and tested in order to identify defects or deterioration immediately”.
The department says in the study, “It will task the industry with developing and implementing an industry-leading code of conduct or standard for the inspection, testing and maintenance of welds for mast crane masts and booms in Nova Scotia.”
The provincial government announced in November 2019 that it would pay $ 2 million to clean up the collapsed crane and reopen the area. The former transport minister said the province was planning to make efforts to recover the money.
A class action lawsuit was filed in October 2019 to set off losses to businesses and tenants.
This Canadian press report was first published on April 22, 2021.