Thank you for all the good and useful comments. Thank you MaterialAg for your help on this. I plan to send correspondence to the university and the system this week.
Mr. Fry, I raised the question because the vertical amplitudes were disturbing and were continuing to increase until folks realized and stopped bouncing. I have sat in most all areas of Kyle Field, and never experienced anything like it. It was and is just that however, a question.
I stated that the answer may very well be that the section is fine and safe for the loading it experienced. I hope that is the case, but it should be looked at critically, not superficially. I will pose that question in as many and all ways available to get action and an answer, because I am concerned for the safety of Aggies and other fans in and below the second deck south end, and could not care less about professional sensitivities,
As to the coming new west side, the geometry, mass distribution, and member section properties are completely different from the south end, second deck structure, which appears to be cantilevered with an edge beam (hence possibly greater amplitudes near the center section). I noticed the south end, second deck structural config. on the construction cams last spring and summer. It looked to be fairly unique.
Similar flexural movement could be occuring near the top of the south end third deck, as noted by others herein. There looks to be a diagonal braced cantilever near the top of that deck. I have no personal experience sitting there.
Some straight forward questions and comments follow. No engineering company should be reluctant to investigate and address the concerns raised in this thread by myself and others.
Was the structure in question, particularly the south end second deck, analyzed for full occupancy with everyone bouncing to Sandstorm or to anything with similar frequency, a little over 2 cycles per second (136 cpm)? (I would look at a range of frequencies around that center frequency.)
If it was so analyzed, what were the results in terms of maximum amplitude of motion and maximum stress, vs. allowables (stress ratios)?
What are the actual amplitudes that are occurring ( as best as can be determined from available video )? (empirical data can confirm or raise questions re analysis and design, or as to whether or not construction was consistent with the design)
If design analysis DID NOT specifically include such loading, it should now be done.
If a problem is identified, it should be corrected with structural stiffening and/or dampers.
If there is not a problem, issue a statement and perhaps signage at Kyle to that effect (enjoy the bounce
There is no place for ego or vanity here, professional or otherwise.
Shelby Meadows, PE
(there, you know who I am now; I have always felt the need for anonymity on this board for a number of reasons, but this is big enough to override any concerns about privacy)
