Laying patio in front of concrete slab pointers?

[mleggatt]

Hi,

I have a wooden cabin sitting on a concrete slab which has an area in front of it that I would like to put concrete 18" x 18" slabs down on.

I want to butt the slabs up against the concrete slab to make a small patio level with the slab (but sloping away from it to allow water run off). A friend had a 1 ton bag of sharp sand which he over ordered, which I now have ready to put under the slabs. I already have about 6" hardcore to lay the sand on top of as a firm base.

Surrounding the slabs I was intending on putting some Terram type fabric down and then cover that with gravel.

I do have a few questions:

1. Should I compact the sharp sand with a whacker plate before laying the slabs on top?

2. Should I add cement to the sand? 6 parts sand to 1 part cement from what I read but not sure if this is necessary?

3. I am concerned that the sand may push out over time from under the slabs into the gravel making the slabs uneven. Should I put some retaining edge stones in to stop this happening?

I have some 24" long x 6" high concrete edging stones I could use for this.

4. If I do use these edging stones do they need to be set in a small amount of concrete to hold them in place?

I know in the past when I have asked questions here on these type of projects I have a tendency to over engineer things . I'd appreciate anyone's advice on this or suggestions on alternatives.

I've attached a diagram to make things clearer.

Thanks
Martin


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[Thermo]

lay them on a wet mortar bed. use the sharp sand in a wet 1:6 mix. that way they wont go anywhere