Big foundation placement specifications

[Mudadi]

Hello everyone,

Does anyone have any specs on placing of big area foundations. I have a foundation for a building 300 feet by 700 feet and I am looking for any aspecifications on placing. Anything would help.

Thank you all

Rain

 

[JStephen]

Not my field...but I'd be looking for a consultant that had done this before, rather than looking for specifications.

 

[rnjroles]

I think more information is needed - when you say big area foundation I assume you are talking about a mat? What type of loads are involved? What type of soil is involved?

 

[Mudadi]

rnjroles you are right. It is a mat, It's for a convention center. the soils are highly expansive soils. I know when they pour the slab they have to pour it in a checker board pattern I think but I am not sure so I am looking for specifications on placing such a huge mat. It's 300'x700'

 

[SlideRuleEra]

Mudadi - Checker board pattern is the time-tested way to go. However you have not told us the slab thickness. What you do depends in large part on that factor.

In general terms you need to size the check board squares based on conditions such as:

1. Concrete volume and delivery rate that can be maintained.
2. Allowable concrete mix design & additives.
3. Surface area that can be finished with the available workforce.
4. Weather conditions.
5. Length of days (unless artificial lighting is available).
6. Provisions for curing the concrete (wet curing preferable).
7. How the concrete will be placed. Cranes? Concrete pump? Direct from truck?
8 Also an overall plan on how each square will be placed, considering that previously poured squares may be in the way.

The specs for the concrete itself and it's placement are often no different than for smaller placements. The differences are the details for the construction joints between the squares and the advanced planning to make larger pours come out as required - if thing don't go well, you will have a very big "mess" to deal with.

http://www.SlideRuleEra.net

 

[jheidt2543]

A few things to think about:

1. SliderRuleEra notes some very good points.

2. Regarding checker board pattern take a look at this
thread 507-127607.

3. For information on large continous pours do a search of on that topic in ENR's back issues. They have at least one good article every year on a large concrete pour.

4. Be sure to have plenty of backup. A standby pump if one goes down, extra finishing machines, etc. The cost of standby equipment is small compared to a breakdown in the middle of the pour.

5. As noted, the timing between the batch plant and the pouring crew is critical, be sure everyone had input into the plan.