Construction consultancy BRE Global has been appointed to examine the wreckage of the Maxima supermarket in Riga to try to determine the cause of its catastrophic collapse.
The supermarket’s roof caved in on Thursday, 21 November, claiming the lives of at least 54 people, the biggest loss of life in Latvia since it gained independence in 1991.
Latvian prime minister Valdis Dombrovskis has already resigned over the incident and a fierce debate is raging in the country over whether building standards were violated and authorities had turned a blind eye.
The supermarket’s builder Re&Re has now asked BRE Global to carry out a full analysis and examination of construction materials at the supermarket once the facility is accessible again.
It’s thought that the independent body will retrieve materials from the site and test them in its laboratory for weaknesses or defects that may have compromised the structural design of the building and precipitated the collapse.
Meanwhile, an independent engineers’ report into the incident, based on construction documents and commissioned by Re&Re, concluded that the maximum load the building’s roof could support was calculated wrongly. It said reasons for the collapse included faulty connections for steel members under the roof and the fact that a winter garden was being installed on the roof at the time of its collapse, according to a news report on baltictimes.com.
The collapse claimed the lives of 54 people Photograph: Dmitrijs Lazarenko/Anadolu Agency/Getty Images
The engineer’s final report will be published after all relevant calculations and laboratory tests of construction materials used in building the supermarket are carried out, said Re&Re.
Toomas Kaljas, a structural engineer working for a Finnish company, has also suggested that the connections between the horizontal bars that held the roof were inadequately designed, and that the garden on the roof, which was only partially built, could have played a minimal role in the collapse.
He was quoted in a news report at Australian new website sourceable.net, going on to claim that the load on the bolts that were holding the bars was uneven and there were too few of them. “A better design would have resulted in components bending and cracking over time, instead of the whole building suddenly collapsing without a warning,” he said.
The building’s owner, HND Grupa, has apparently acknowledged that trusses made of two pieces bolted together were used, rather than the single truss specified in the original design, due to difficulties transporting longer trusses to the building site.
But such an alteration should have required that the entire design be revised and re-approved by the authorities, claimed Lilita Ozola, an engineer teaching at the Latvian University of Agriculture, also quoted by sourceable.net. Ozola said the joint between the two-piece trusses would bear most of the roof’s weight and that video footage of the disaster clearly showed failure at the precise position of the joints.
