Design Flaw???

[BigFish]

Alright! I have seen the video of the area where the panels collapsed......heard all the discussion and theory of why it happened! They are saying it was either the improper installation of the bolts which were epoxied into place? (Epoxied???? That sounds bad!) Or the epoxy was old and brittle????? (Old and brittle????Did they think this stuff was going to last forever and get younger and stronger???) I want to know when we are going to hear the phrase...."Design Flaw" used? Poor engineering in my opinion caused this tragic event! A guy from MIT did a demo on the news tonight showing what happened on a small scale model. Naturally what happened was the bolts supporting the panel from above center let go and the weight dispersement was sent to the supports on the side walls and these then gave way causing the panel to release and fall. I have several questions in regards to this design.

1. Why did they use cement slabs instead of a fiberglass panel? Fiberglass would offer soundproofing, easier installation and maintenence, support would have been a non issue.....not to mention perhaps more cost efficient if not in the beginning perhaps over time.

2. Why was the panel supported from above by a single bolt and cable which was drilled into the cement above and epoxied into place as opposed to having the bolt or a threaded rod installed permanently in the ceiling above via a metal plate perhaps when it was built?

3. The design shows support on either end via tie bars and a single cable support from above but the bulk of the weight of this slab/panel resides in its length and I have to wonder why there were no angle supports length wise between each panel as added support???

It just seems to me that the design of these panels is flawed in every way and these "brilliant" engineers who designed it used no common sense what so ever in the design of this portion of the tunnel and I can't wait to hear the words "Design Flaw" because that in reality is what is at issue here! Not the installation....not the epoxy...(though I think both may be suspect in their own right) it is the design which proved fatal....and unfortunately so!

Any thoughts?