Engineering Errors Contributed to Tower Collapse

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UPDATE ON DECEMBER 5, 2018

Per the editor:

In our November 26 article, Contractor’s Error Caused His Death, OSHA Reports, we heard from associates of Mr. Lemay and those who had a deeper knowledge of the KOZK tower collapse in Missouri who felt the headline didn’t focus enough on errors by the engineer/contractor, TCI, that were leading contributions to the accident.

The OSHA report cited four issues in all for the collapse, two of which were attributed to the consultant, TCI, and two to the contractor, Mr. Lemay.  The report stated “TCI’s suggested diagonal replacement procedure was flawed….and weakened the legs.” Our respondents, who wish to remain nameless, point to this issue as the major cause of the collapse.  They told Inside Towers, Steve wasn’t a contractor that took shortcuts and emphasized how conscientious he was. In this case, they said he was following the diagonal replacement procedure indicated in the drawings that the engineering consultant (TCI) produced.

While Inside Towers reprinted the OSHA findings verbatim, if we had to do it all over again, the headline would have read; “Engineering Errors Contributed to the Tower Collapse.”

UPDATE  The collapse of the 1,890-foot KOZK tower in Missouri and resulting death of contractor Steve Lemay was recently ruled on by OSHA, as to the cause of the accident.  The report was obtained and published by Current, per its request of the documents, through the Freedom of Information Act.

In April of 2018, Missouri State University (MSU) contracted Tower Consultants, Inc. (TCI) to design the required structural modifications necessary to support the transmission line replacement.  MSU owned the KOZK tower, an 1,890-foot guyed tower along Highway FF north of Fordland, MO. TCI’s scope of work involved creating construction documents, reviewing submittal drawings, observing the construction process including producing progress reports and assisting MSU in the bidding and contractor selection process.  MSU selected Steve Lemay, LLC to serve as the contractor.

During the renovations, the tower collapsed, killing Lemay and injuring three others.

OSHA cited missing bolts and a sub-standard winch used by the contractor as the cause of the collapse.

Conclusion: OSHA Report issued in October 2018. “Investigation of the April 19, 2018 Communication Tower Collapse in Fordland, MO:

Based upon the above, we conclude that:

  1. TCI’s suggested diagonal replacement procedure was flawed in that it compromise the effectiveness of the integrated surrounding braces and the load bearing capacity of the tower legs.  A single diagonal brace could not be removed without affecting the integrity of the redundant brace because the braces share two common bolts at the diagonal/redundant connection.
  2. The cause of the communication tower collapse was the weakening of the compressive strength of the tower legs by removing the bolts at the connection of the diagonals to the horizontal redundant.  The compromised redundant effectively doubled the unbraced length of the tower leg which reduced the compressive capacity of the tower leg.
  3. Lemay used an undersized come-a-long while removing the diagonal braces.
  4. Lemay failed to provide the design of the required temporary frame for diagonal replacement above or below a guy level.  TCI failed to confirm the use/design of a temporary frame as TCI is required to approve the adequacy of the temporary frame prior to diagonal replacement according to TCI’s construction documentation”

An attorney for Lemay’s widow, Carol Lemay, told OSHA in an email dated October 16, she will close the business December 31.

Sample from the collapsed tower of the type of bolts that were removed by the contractor and the hoist equipment ruled inadequate for the job by OSHA  Source: OSHA Report

By Jim Fryer, Managing Editor, Inside Towers

November 26, 2018