Sand Base For Concrete Slab

Difficult to maintain a flat level sand surface during concrete placement difficult to.

Sand base for concrete slab.

A typical pad has a 4 inch layer of gravel underneath and about 4 inches of concrete on top. From american concrete institute aci360r 10 guide to design of slabs on ground 4 5 design of slab support system 4 5 1 general after subgrade soils have been classified the general range of k values can be aproximated from fig 4 3. When building a landing for deck stairs typical codes require the pad to extend beyond the steps about 36 inches behind the steps about 12 inches and on the sides of the steps about 6 inches. It plays an important part in the concrete s composition.

Almost 20 years ago concrete construction investigated the effect of using a layer of loose uncompacted sand directly beneath a concrete slab and concluded that this practice contributed to more later age cracks and poorer joint performance here are the reasons not to use a sand layer. However you then need to create a frame fill with stone mix cement level and allow to set. 100 sieve with no clay silt or organic materials. Laying a concrete shed base involves the same clearance and levelling of land as with a paving slab shed base.