Do we need Geotechnical for all the soil process? 1

[July2007]

We are specifying a concrete pad with the size of 7'-6"x 6'-6"x 1'-6" deep, to install and secure 2-3 electrical and communication panels, weighs approx 200LBS-400LBS.

Is it necessary to provide Geotechnical sampling and test for this type of facilities?

Location will be in Barksdale AFB/Shreveport-Louisiana.

Thanks,
Mano

 

[dgillette]

You should probably do a backhoe test pit - cheap - to be sure you don't have a layer of bad stuff (v. soft clay or organics) within a few feet below the slab. Never been to Shreveport (or LA at all), but there are soft deltaic deposits in that part of the world, sometimes with organics. I would guess that a little differential settlement could be tolerated for electrical panels. With a heavier structure or one that was very sensitive to movements, you would require more investigation, of course.

 

[BigH]

good advice from dgillette - but if on an airforce base, I am sure that they have soils data from nearby structures which might be a bit more involved. You should check out for any previous investigations that they might have - then can make judgment as to whether any other consideration is needed. with only 400 pounds on a foundation that is nearly 8ft by 6 ft in size, it is quite you are in effect not putting on any load other than an extra 100 psf from the weight of the concrete itself.