Collapse of Concrete Side Panel Marriott Montreal

Comprehensive investigation into the causes of the failure that led to the collapse of a concrete side panel and recommendations provided to the coroner for the appropriate inspection, maintenance and repair of the building

On July 16^th 2009, a concrete side panel detached from the facade of the Marriott Residence Inn Hotel in Montreal, and fell from the 18^th floor, killing one person and injuring another. Following the accident, a portion of the street was closed to traffic and reopened once the façade panels were secured in place.

SIMCO was hired by Paul Croteau & Associés (PCA), and Stikeman Elliott (SE) to evaluate the condition of the precast concrete panels (detached and in-place panels) in order to determine if the panels were durable and could be left in place for many more years.

The analysis performed by SIMCO’s experts was part of a larger investigation to evaluate the condition of the panels and to determine adequate corrective measures to be implemented in the short to long-term.

SIMCO’s scope of work included on-site inspections and measurements on selected panels and anchors, determination of the location of the steel reinforcement, and corrosion activity measurements.

SIMCO also performed a comprehensive laboratory testing program to fully characterize the concrete of selected panels in order to estimate the residual service life of the structure and provide a short-term remediation plan to ensure the safety of the building.

The results of the investigation indicated that the corrosion would most likely continue, especially around the old anchors, which may lead to the delamination of concrete pieces that could eventually become detached from the panels. It was therefore recommended periodic inspections be performed by the owner’s experts to monitor the evolution of the facade’s condition and assess the efficiency of the corrective measures.