Slab Resistance 2

[BadgerPE]

In designing a shallow foundation with the floor at the bottom of the wall and the soil on the exterior at the top of the wall (building is open with no interior walls to add rigidity). How can I quantify the amount of resistance the floor slab will have to resist overturning? Currently my overturning moments grossly outweigh my resisting moments and I need to rectify the situation before I can continue. Thanks much!

 

[ishvaaag]

If continuous with the wall, the slab provides stability. Determine the moment and shear requirements for the slab from its connection to the wall under the earth push ar the proper overturning required factor, 1.6, 2 or whatever, and if the slab is properly reinforced to take the standing solicitations, and you don`t see anything wrong anywhere in the model, you are safe enough against overturning. Like modeling a vase of a pool.

 

[msquared48]

The slab will have the most impact in resisting sliding, but very little against overturning unless the slab is cast integral with the footing of the wall itself, and properly reinforced to take the moment from the wall.

Picking up additional dead weight by increasing the length of the heel could help if it is possible. If not, then you are probably dealing with an inefficient "L" shaped retaining wall, the design of which is very limited by the allowable soil stress.

Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask