In the Military there is a long standing tradition that you do not march soldiers over a bridge in step. When marching and approaching a bridge the command of Route Step, MARCH is given. This command keeps the soldiers marching in formation, but every soldier is allowed to march at her/his own step. Although this is widely practiced in the Army, I found very few who knew the reason why.

What could have possibly prompted this tradition?

I had always heard that the route, step, march order was done after a column of British soldiers caused a covered wooden bridge to collapse in the 1700's, but I can't find any reference to that online.

I had also heard mention that the colapse of two catwalks in the Hyatt Regency Hotel in Kansas City, MO was also caused by resonant frequencies, but further inviestigation seems to indicate that the cause of that collapse was improper construction.  It is possible that the 50 or so people on the cat walk may have been stomping their feet in unison which would have caused greater momentary stresses on the botls holding the catwalks.

Possibly the earliest recorded incident of people using resonant frequencies to cause structural collapse is in the story of the city of Jericho in the Bible.  In that story, the Hebrews marched in unison around the city one each day for a week, then on the seventh day they marched around the city 7 times with a trumpet blast (if memory serves me correctly).  It is at this time that the city walls coallapsed.  Of course it is also quite possible that an earthquake occured at the same time causing the collapse, but there is no way of proving that.

Edited on April 18, 2005, 3:31 pm

Posted by Erik O. on 2005-04-18 15:30:19