Please no one take offence, as none is intended, but may I make a gentle request - if you are going to continue with this string, but along lines that are not relevant to my question, perhaps you could start a new string, as every time you send a new message it shows up on my email. Thanks. Much...
Yes they are un-bonded tendons. I am posting this all for another engineer in the office, so thank you all for your comments, which I will relay to him, including about how to make the opening. It is great to have comments that stay focused on the question at hand. I will convey all these...
Ingenuity - we have x-rays. The hole will be enlarged by core drilling, not sawcutting. There are top and bottom rebars in the slab at the sides of the opening so jack hammering down from the top of the slab to locate the tendons would not work.
I sent my last message (in response to BARetired before I read TehMightyEngineer's message. I think TehMightyEngineer's is saying essentially the same as I said.
That is what I was thinking, but bearing in mind that the opening is to be enlarged in both the north-south AND the east-west directions, the tendon may exert a lateral force on the concrete within the length of the enlarged opening (depending upon where the bend on the tendon is located...
There is an existing opening 51" x 24" thru an existing post-tensioned slab. They want to increase this by 1.5" each of the 4 sides, at each of a number of floors, for a larger size duct, so that the opening will become 54" x 27" (see attached). We have had x-rays taken of the tendons. We have...
I have read of a precast system of unusual design that stood up fine for many years and then suddenly the floor collapsed. The investigation indicated that the original design missed an issue that was critical because of the odd ball design. Some other floor structures that were built around...
ddudley - Very interesting. I thought from looking at the pictures that I found on the internet, that the spandrel had given way. What you say seems to indicate that may have been the case. Kind of scary that they could forget to complete the angle connections with the weld. Have you heard...
It looks like hollow core, not precast double tee. Right? Elliott Lake was also hollow core. Maybe this is a good thing to stay away from for garages. Still, I would like to know what the cause of the collapse was.
Has anyone heard about a reported partial collapse of the 5th floor of a precast double tee garage in Houston, Texas, in June? If so, does anyone know anything about it, like how old the garage was and whether corrosion was in any way a contributing factor? If not, what was the cause? Any...
Just to let you all know, I contacted Boise Cascade in Canada and they have special software for Versalam, and the special properties for Canada which are different than U.S. and of course the Canadian are LSD. Also, it is Chapter 13 of CSA O86 that deals with these proprietary wood products...
If I may return to my original question, about whether any limit should be specified on the length of pour of slab-on-grade, to avoid slab performance issues, or excessive opening of the joint between pours when the slab dries out: Is it the consensus that there should or should not be such...