Cedec/imag self binding gravels - Cedec/imag self-binding gravels

[mjc]

Hello,

Has anyone got any experience with Cedec or IMAG self-binding gravels?
What is the difference between these products?

CED's website says I should use a non-vibrating roller - how suitable would a compator plate be for a garden path?

Is there any need for a binding layer between MOT1 and the gravel layer (as recommended by IMAG)?

Finally, how important is it to install an edging all the way down to the sub-grade (to prevent the sub-base from migrating side-wise) when using self-binding gravel?

Thanks

[GB_Groundworks]

Pretty self explanatory

Paste

Coverage of CEDEC® is approximately 10m² per tonne, compaction being about 25%.

The following specification is based on best practice and may vary according to the particular situation.

Specification and Maintenance - Foundation
The foundation layer should be laid to a uniform crossfall or crown as required on the finished path. This layer should be firm enough to take the subsequent layers and compacting machinery without deformation and a geotextile should be used if ground conditions so indicate.

The thickness of the base layer will depend on the maximum vehicle weight likely to cross the footpath gravel but a compacted 150mm is suitable for pedestrian and light maintenance vehicle use. A free draining layer of specially graded 28-0mm from the same source as the surface layer is the best practice, however other inert materials with similar sizing may be suitable. A 1500kg non-vibratory roller should be used, but being careful to avoid damage to irrigation systems if installed. If any irregularities are found in the base layer, these should be rectified with the correct base layer material and not the surface material.

CEDEC® footpath gravel should be supplied in a thoroughly mixed and moist state. It must not be laid if dry and should be laid to a thickness of 50mm after compaction. Initial compaction should be carried out BEFORE watering takes place and by at most two passes of non-vibratory roller not exceeding 500kg in weight. After initial compaction, which should be sufficient to prevent fines being washed through the surface, thorough saturation is necessary with water by a hose fitted with a rose sprayer, or similar method, taking care to prevent disturbance of the top layer.

Final compaction of the saturated surface (5 or 6 passes) is to be with a non-vibratory roller with a 500kg axle weight on the saturated surface. A short delay (up to 30 minutes) may be necessary after watering to prevent pick-up on the roller. Two further cycles of watering and rolling (5 or 6 passes each) should take place within one week after lying.

So no a plate compactor is not suitable as it's a vibrating compaction force.

As for imag it's a blinding layer not binding, don't see why you need it with a good dtp1 mix but spec is bit crap, I'd just go with 100mm dtp1 then your gravel with 150mm edgers to retain it all in.

http://www.imag.co.uk/downloa....s.pdf;)

[mjc]

Thanks, Giles.

I understand that a non-vibratory roller would be ideal, but given rather limited space for a roller in my garden, would a plate compactor be good enough for light foot traffic?

Is there any difference between IMAG's and Ced's gravels?
Cedec looks slightly more expensive.