Precast Design
Precast Design
(OP)
I have got to design this precast building,and being new to the precast (never designed precast building before), I am wondering who is actually responsible for designing primary structural members such as precast beams and columns (EOR or precaster's engineer)? Can anyone with precast experience help clarify roles of EOR and precaster in a typical precast building project?
Thanks in advance.
Thanks in advance.






RE: Precast Design
RE: Precast Design
RE: Precast Design
RE: Precast Design
http://www.precastbuildings.com/
RE: Precast Design
If the intent is for the precast wall panels to act as shear walls, you will have to be very specific in terms of how the shear is transferred. One issue that I have run into is that the precaster will tie some panels together, creating "stiff" elements in the wall line.
Another issue is relates to the use of the panels for girder bearing. If the panels are not designed to transfer load from one panel to the next, you can have greatly varied soil pressures.
RE: Precast Design
Any details that relate to the erection of the panels need to be provided by the precast manufacture. Ie. Any lifting eyes or additional reo for lifting etc
RE: Precast Design
The building I am working on has double tee roof with precast columns and pocketed spandrel beams where they support tees. Facade will have architectural precast panels with continuous ribbon windows all around, so I am thinking of making beam-column joints rigid to resist wind and seismic forces. But I am not sure if I needed to design the frame members or precaster would design it. Another dillemma I have is if precaster is responsible to come up with the design, what beam/column sizes I use to perform my lateral analysis. Do I perform a prelim analysis to come up with approx. sizes and use them in my lateral analysis?
Thanks,
RE: Precast Design
RE: Precast Design
If you are talking designing a pre-cast structure as a tilt-up type structure to be built on site, then it is you who designs eveything except that the contractor should be responsible to take care of any modifications to the pieces that may be required for lifting and erection (inserts, stiffeners, etc.).
RE: Precast Design
JD2, your post helped clear a lot of things, thanks everyone!
RE: Precast Design
RE: Precast Design
It is your job to spec out the general arrangements and the loadings as described. That does include basic sizes, sections and the levels. If you do not have a copy of the PCI manual, you will need one. It has some basic tables, connection details and panel parameters that will probably help.
If you want to give them the flexibility to adjust the sizes for cost efficiencies, you can define that in the bid documents.
As for 3D models, yes some do create them in the US. There are a few that have some incredible websites with all their standard details also. You need to do some research.
A key for success with PC can also be getting them involved sooner in the process than other projects. The one downside of PC is delivery. Our plant is typically reserving space for projects 3months after you sign on the dotted line.
Brad
RE: Precast Design
Brad, thanks for your insight. I actually recently contacted one local precaster, a potential bidder, and got similar input. Great point regarding getting the precaster on board earlier in the process in connection with the schedule. We are thinking along similar lines and going to suggest the owner for the same.
Thanks guys,