Remember that embarrassing incident on March 14, when a 300-tonne span on the Evergreen Line SkyTrain guideway over Como Lake Ave. shifted?
Luckily, there were no injuries.
It happened just a week after Premier Christy Clark appeared at a March 7 photo op to activate Alice, the tunnel-boring machine.
The incident investigation report, released to me via Freedom of Information, tells the story about what happened, from the perspective of EGRT Construction, the project team led by beleaguered engineering and construction giant SNC-Lavalin (whose 2013-retired chair, Gwyn Morgan, was named by Clark to chair the B.C. Industry Training Authority).
Two so-called “failure scenarios” were investigated, with the report citing lateral movement at pier 56 “first causing redistribution of loads at pier 56 crushing the concrete spacer” as the most likely.
Said the recommendations to prevent a repeat:
“Regardless of the failure scenario, the following corrective actions will be implemented to prevent a recurrence of such an incident.
“In addition to the standard erection plans for typical spans, site specific temporary support plans shall be designed at all non-typical locations and areas of high grades and cross-slopes, identifying shimming materials and configuration, use of wedge plates, hydraulic jacks and provisions for additional lateral restraints if required.
“The site erection engineer shall review all temporary support set-ups and confirm they meet the design.”
The $1.43 billion project is expected to be open in 2016. See the investigation report below.