Monday, April 20, 2009

April 20th, 2009

Bellevue Washington. The November 2006 crane collapse caused the death of Matthew Ammon. I was a crane erector on that crane. I/we complained of the problem that led to the collapse of that crane and have been subsequently deposed. I was set to give testimony in the Ammon Trial. Matthew's family had sued two companies involved with the crane, the general contractor, Lease Crutcher Lewis, and the engineering firm that designed the steel base for the crane, Magnusson Klementic. During the crane erection we noted movements in the base of the crane exceeding normal acceptable tolerances. We stopped, huddled at the base of the crane, got the measurements, informed the general contractor of the problem, calls were made then we were told to proceed, this had been planned for. 
Reality... Tower Cranes must be erected to a deviation of plumb not greater than 1 inch of deviation for every 40 feet (more accurately 1:500). The same is true for the horizontal plane. Normally when we set a base we allow an 1/8th inch of deviation in the 8 foot span which will keep us well within tolerance. The deviation that day was 1 inch in the 8 foot span. That equates to >5:500 which is well beyond nationally accepted design standards established in ASME B30.3 2004. The crane base was deflecting to this deviation over and over depending on the moment load of the crane at any given time. Metal Fatigue set in and the crane eventually ripped one of the beams it was mounted to. The design or the execution of it was effed up from the begining as I had stated during the crane erection. 
Attorney's and the system that we have doesn't ferret out any better truth than we had the following day. No one has earned more by hiring attorney's with the possible exceptions of MKA and LCL. It's too bad that we live in a system where it takes 2.5 years for obvious truth to be owned up to. I hope that the Ammon Family finds peace and they know that we have improved as an industry. I will see to it that we continue to improve nationwide as well.  

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