ND?
equipment. Therefore why not use bagged kiln-dried sand?
Answer 5
The cost of appropriately large quantities of bagged kiln-dried sand is prohibitive.
Where it has been used, the schemes inevitably have installed very limited quantities of the sand and, as a result, they provide very limited benefit.
NO, kiln dried sand is not a cost- effective option. Equipment which cannot handle moist sand should be replaced by modern machines which can do so.
Question 6
Haulage. What size loads? Answer 6
As large as possible. The price per tonne is higher for smaller quantities.
It is usually advisable to order sand in loads of at least 20 tonnes.
If a little is left over afterwards it is useful material to have in stock and it is very frustrating to have to obtain another tonne or two in order to finish a job.
Question 7
If the right sand is hard to obtain, is it alright to use gravel or granules instead?
Answer 7 DEFINITELY NOT.
Although gravel or granules or grit may be used as backfill at deeper levels, these materials are not suitable as backfill up to the surface.
The pore spaces in such materials are comparatively large so it is all too easy for fine soil particles to infiltrate into these voids and reduce permeability to zero.
As a result, gravel slits or “bands” are soon capped and cease to work.
Sand has many times more numerous but smaller voids between its much smaller particles and this lack of size inhibits the ingress of fines.
Therefore, sand slits continue to function for a much longer period than gravel ones and so are substantially more cost-effective.
Furthermore, gravel at the surface is a hazard to play and also it is seriously detrimental to the soil texture of the
Sand for Sand Slits
8 key questions and 8 Key answers By GEOFFREY DAVISON
root-zone.
In contrast to the adverse presence of gravel, sand provides long term benefit to the playing surface and to the texture of the root-zone soil.
Question 8
If good sand is too expensive is a cheaper, less permeable sand a reasonable alternative?
Answer 8
A particle size analysis of the lower priced sand is required before a
valid answer can be given. Factors to be considered are:
1.Tested hydraulic conductivity.
2.Percentage distribution of the particle sizes.
3.Uniformity of particles. 4.Suitability for machine handling.
The lesser the hydraulic conductivity the more intensive a scheme design has to be in order to achieve an acceptable drainage rate.
Whether a cheaper sand is a reasonable alternative depends on the results of the analysis.
the price of a not so good one
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