PARKING GARAGE COLLAPSE


Areas of expertise include structural engineering, construction engineering, evidence tracking, project documentation analysis, review and planning, and interaction with local and Federal agencies.

Scenario

A six-story pre-cast concrete parking garage under construction and nearly 75% completed in Miami, Florida, suddenly collapsed, killing four construction workers and causing severe injuries to many others.

ProNet Group was retained in this $32 million plus loss by the general contractor’s primary and excess surplus insurance carriers to serve as Project Manager and leading investigation firm for the multi-party joint investigations to determine the cause of the catastrophic structural failure and collapse.

A number of potentially liable and other interested parties were involved in this complex large loss investigation, including the crane operator, original engineer-of-record, manufacturer of the pre-fabricated concrete structural  members, geotechnical testing lab, and threshold inspectors, to name a few.

The on-site investigation of the accident scene lasted for over a month. ProNet's experts documented, photographed, and conducted 3-D laser scans of the rubble to identify and survey the area, and to electronically preserve the overall condition and the exact locations of the buried structural members.  Additionally, the pre-existing adjacent structure was evaluated to verify if it sustained damage.

Command Center

ProNet established an on-site command center that served multiple purposes.  Initially, the site was considered a crime scene, and for approximately ten days ProNet’s team worked in coordination with Miami-Dade fire rescue and Miami-Dade police by conducting structural assessments, and monitoring the structure to assist in the search and recovery of the last victim and stabilization of the existing structure.  ProNet was able to offer this unique additional service as certain members of our engineering staff are registered as Structures Specialists with FEMA Urban Search and Rescue.

Upon completion of the initial stage, the use of the command center was converted to hold multiple daily progress meetings and stage the planning of deconstruction efforts.

Deconstruction and Evidence Tracking

During deconstruction of damaged portions of the structure, ProNet identified and labeled the members of the rubble and collected material samples such as reinforcing steel, grout plates, and others.  Additionally, ProNet witnessed and documented coring samples of certain cast-in-place and pre-cast concrete members, and surveyed shoring and bracing to the still standing portion of the structure to determine integrity and safety.

Additionally, ProNet’s construction experts were called on to serve as the Evidence Tracking Manager.  ProNet developed a location code system for tagging purposes and easy location identification of the specific structural members of the building and its location within the structure (beam, column, floor level, etc).  For nearly two months, we witnessed, photographed and tagged construction portions of the partially collapsed structure prior to them being safely disassembled.  The process included identifying, marking, and documenting individual pieces and members of the failed structure, photographing the evidence prior to leaving the site, and maintaining the condition of failed and deformed members during transportation to the boneyards.  The transported members were then documented and photographed upon placement in the boneyard.

Boneyard

An available vacant lot was selected to serve as the boneyard where the evidence was moved and stored.  The site was chosen due to proximity to the accident site, was properly secured and fenced, had good topography for storm drainage purposes, and offered plenty of room for placement of the members and allowing multi-party experts to continue with their investigation.  ProNet devised an ID system for each pre-cast member that would allow for identification of where the piece was originally discovered at the accident scene and where it was located in the boneyard for additional examination.  Additional evidence preservation included over eighty (80) separate structural members from columns and beams, spandrels and Double-T columns, and other structural and construction components.

Outcome

After nearly three months of investigation, site deconstruction, and analysis of the evidence, it was determined that an interior bottom floor pre-cast concrete column suffered from an installation defect which resulted in a progressive structural failure and eventual catastrophic collapse.  The parties ultimately settled prior to trial.