tilt up concrete panels

[structuralnerd]

Has anyone designed tilt-up panel concrete walls before? I have some great design examples that I am using out of the ACI 551 code, but it does not go through any thorough analysis of connections. I have a one story building about 24 feet tall, and each panel is approximately 20 feet long. What is the best way to connect the panels to a foundation wall? Embedded plates and headed welded studs? Also, to prevent the panels from overturning, is there anything extra I need to do at the ends of the panels? I have already put additional reinforcement in the ends of the walls, but is there a good way to connect it into the foundation? Also, the code recommends to connect about every 2 or 3 panels together. Is that an industry standard, or should I be aware of something else? Any help would be much appreciated. Thanks.

 

[kajn]

You need to get a book called, "Design and Typical Details of Connections for Precast and Prestressed Concrete" it is by the Prestressed Concrete Institute. Here is a phone number 312-786-0300. This book has many typical connection details.

 

[JedClampett]

There are several choices, from the simple (setting the panel on a bed of grout) to the more elaborate (dowels, angles attached with expansion anchors, etc). It all depends on your shear reactions, in both directions, at the base, personal preference and constructability.
Get a copy of "The Tilt-Up Design and Construction Manual" by Hugh Brooks. You can order it from the Tilt-Up Concrete Association. It has a selection of details and where they are appropiate.

 

[hokie66]

See also the references youngstructural gave in response to another query about thin walled structures. Couple of days ago.

 

[youngstructural]

One further comment about tilt-up buildings: For a building with a regular layout, and without too many open two storey ceiling height areas, you don't always need a braced roof or diaphragm action at the roof level. Check your analysis; You'll probably find that you can cantilever the tilt-up wall past the last floor to carry the last floor's walls.

Good luck,
Let us know how it goes,

YS

B.Eng (Carleton)
Working in New Zealand, thinking of my snow covered home...

 

[haynewp]

We used to always have a grout bed on top of the footing and have dowels that go back into the slab into a pour strip. But as Jed mentioned, there may be more that is required (I have seen embeds at the base of the panel with expansion bolts into the footing also). We would also connect panels together when in-plane overturning was high enough and there was not sufficient dead load.

You should also check whatever your code is to see if there are minimum connection requirements.

 

[csd72]

See 'Connections for tilt-up Wall Construction' by the tilt-up concrete association

http://www.tilt-up.org/resources/literature.html

You will probably find that prevention of outward collapse in a fire governs much of the connection design.